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No sparky, what to look for next?


TimberGuy

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Sorry about another "won't start" thread, but I need some help to get my rebuild on the road. Stumped and hope the collective can offer some guidance (situation not seen on other threads here that I have found yet).

 

97-R1100RT with 164k miles and has been owner wrenched for many years. Just completing rebuild except for engine and transmission which were left unopened, still needs a throttle body synch. Started and ran well (be it a little rough) for a short test ride. Had an odd dash lights issue that was solved when I corrected a mis-labeled pair of connectors under front fairing; had connected "handle heater" to rear brake level causing Fuse 1 to blow. That involved a careful scrutiny and re-wrap of entire harness forward of gas tank, no other issues found. After that it started and ran well for several minutes sitting in shop to conclude the day (no test ride). Back on the trickle overnight.

 

Next attempt to start gets starter cranking but no sparky (confirmed with removed plug). Did not touch the bike between the running test and next attempt. I did have a 2-pair lead that I think should be connected as grounds to Motronic mount bolts, have connected one of those but the other does not read as ground on ohmmeter so it is still unknown / free (colour = brown with green line, only unspecified wire to me on bike).

 

Battery is Odyssey and reads 13.5 v and has been trickle charged most of the time when not in use.

During early test ride, the alternator did start and batt terminals registered 14.04 v.

After reading other thread I checked Throttle Position Sensor and connector is tight / dry.

 

I am stumped and worry that Motronic has somehow suddenly gone bye-bye. Can't understand how lack of ground on bolt would do that however. HES presumably ok because of previous successful test ride. What am I missing?

 

Thanks in advance for any ideas or questions.

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OK, that request flew like a lead brick.

Maybe a couple of focused questions.

 

1) Is there any way for me to check and see if the Motronic is operating (at all or properly) here at home? Does this require a special diagnostic tool at a dealer as the manuals (Clymer & Haynes) infers? Can I put a voltmeter into the coding ports of the fuse box and learn anything? Would be nice know if it is just confused, or dead.

 

2) Is there a resource for in-depth electrical information on these bikes? Everything I've seen so far is "mechanical" in focus with a hope / faith / expectation that the electrical side will just do its thing when the time comes.

 

3) Is there any other electrical device I need to check for operation that feeds the Motronic and tells it "ok to send spark"? I have shorted across the side stand switch so it is always open. I have checked the handle bar kill switch and it seems to be working.

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greiffster

Randy,

I'd start with verifying that HES. Just because it was OK one day may not mean it's good.

 

I've heard the wire harness near the handlebars up to the ignition can cause problems. Any chance you go something short in there after you re-wrapped it?

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Afternoon TimberGuy

 

Have you checked for (key-on) 12v to the ign coil green wire? If not then start there.

 

If no 12v power to the coil then we will have to address that side of the primary system.

 

If 12v to the coil then check fuse #5 for continuity as well as power to & through fuse #5.

 

Does headlight come on at key on then go off during engine cranking?

 

Do you have (key-on) 12v power to the green wires at the fuel injectors?

 

Do you have (key on) 12v power to the 86 terminal of the motronic relay? (in fuse box)

 

No good (easy) way to test motronic in a bike that won't start. Best way is to just plop it into a bike that runs. Otherwise you will have to test & verify each & every circuit into & out of the motronic.

 

Do the above verifications then we might have a direction to take from there based on what you find or don't find.

 

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Hey, thanks guys - that gives me something to chew on for sure.

Not able to get back to bike for a day or two, but will report again soon.

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  • 3 weeks later...

I'd start with verifying that HES. Just because it was OK one day may not mean it's good.

HOW TO? PULL THE CONNECTOR AND CHECK FOR ZERO OHMS AT SOME POINTS DURING ENGINE ROTATION?

HAVEN'T DONE ANYTHING WITH THIS YET.

 

 

Have you checked for (key-on) 12v to the ign coil green wire? If not then start there.

YES, 12.40v ON THIS WIRE. BATTERY ON TRICKLE FULL-TIME EXCEPT WHEN I AM TESTING SOMETHING.

 

If no 12v power to the coil then we will have to address that side of the primary system.

 

If 12v to the coil then check fuse #5 for continuity as well as power to & through fuse #5.

YES - CONSTANT 12V SUPPLY TO FUSE #5, FUSE IS GOOD (IMPEDANCE CHECK ZERO).

 

Does headlight come on at key on then go off during engine cranking?

YES AND YES.

 

Do you have (key-on) 12v power to the green wires at the fuel injectors?

YES, BOTH.

 

Do you have (key on) 12v power to the 86 terminal of the motronic relay? (in fuse box)

MOST AFT PRONG (TRANSVERSE ORIENTATION) HAS CONSTANT 12V SUPPLY, RIGHT SIDE LONGITUDINAL PRONG HAS 12V AT KEY ON AND I CAN "FEEL" IT TICKING.

HAVE SWAPPED RELAY WITH ADJOINING AND NO CHANGE IN RESPONSE.

DON'T KNOW WHAT "86 TERMINAL" REFERS TO, RELAY PRONGS ARE LABELED 1, 2, 3 AND 5.

 

No good (easy) way to test motronic in a bike that won't start. Best way is to just plop it into a bike that runs. Otherwise you will have to test & verify each & every circuit into & out of the motronic.

 

Do the above verifications then we might have a direction to take from there based on what you find or don't find.

 

OTHER INFO:

- I HAD 2 UNKNOWN WIRES, A PAIR ON LEFT SIDE JOINED TO MAIN HARNESS JUST ABOVE LEFT INJECTOR. BOTH BROWN, ONE WITH A GREEN DASH STRIPE. I BELIEVE THESE ARE THE TWO GROUNDS THAT SPRING FROM THE MOTRONIC MOUNTING PLATE AND I HAVE FASTENED THEM THERE. INITIAL TEST RIDE AND OTHER RUNNING WAS DONE WITH THIS UNCONNECTED. IS THE PURPOSE OF THESE TWO TO SHORT ANY STATIC BUILDUP ON THE MOTRONIC CASE?

 

ARE THESE SIGNS POINTING TO PROBLEM WITH IGNITION COIL?

DO I NEED HES VERIFICATION TO CONFIRM THAT COIL IS GETTING A "FIRE" SIGNAL?

CAN I, WITH SIMPLE DIGITAL MULTI-METER, SHOW THAT COIL IS GETTING COMMAND?

 

SO CLOSE, AND YET SEEMS SO FAR. THANKS IN ADVANCE.

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greiffster
I'd start with verifying that HES. Just because it was OK one day may not mean it's good.

HOW TO? PULL THE CONNECTOR AND CHECK FOR ZERO OHMS AT SOME POINTS DURING ENGINE ROTATION?

HAVEN'T DONE ANYTHING WITH THIS YET.

 

 

You can test the HES sensor with a GS911. Do you happen to have one?

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Have GS911 enroute. Not a lot of discussion about them online - I hope it lives up to the hype (I realize it is just a diagnostic tool and won't do magic). Will be nice to have some kind of diagnostic ability here in a home shop.

 

Bike is still laughing at me as it sits in the nice clean shop avoiding the hot dry road.

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With Hager Report (2004) as guidance to HES repair, I started opening up the front end. As suggested before going further, the ignition coil was first to be examined.

Whadayaknow - the secondary coil shows an open circuit, not the required 13k ohm resistance. (The primary read 0.6 ohm.) Replacement en route.

 

How common is this failure (ignition coil)?

Did I do something that caused it during my rewiring and testing?

Will know more next weekend.

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With Hager Report (2004) as guidance to HES repair, I started opening up the front end. As suggested before going further, the ignition coil was first to be examined.

Whadayaknow - the secondary coil shows an open circuit, not the required 13k ohm resistance. (The primary read 0.6 ohm.) Replacement en route.

 

How common is this failure (ignition coil)?

Did I do something that caused it during my rewiring and testing?

Will know more next weekend.

 

As these bikes get older I have noticed that coil and wire problems are becoming more common.

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With Hager Report (2004) as guidance to HES repair, I started opening up the front end. As suggested before going further, the ignition coil was first to be examined.

Whadayaknow - the secondary coil shows an open circuit, not the required 13k ohm resistance. (The primary read 0.6 ohm.) Replacement en route.

 

How common is this failure (ignition coil)?

Did I do something that caused it during my rewiring and testing?

Will know more next weekend.

 

Morning TimberGuy

 

The BMW ignition coil is a very robust coil that very seldom fails. About the only thing that will kill a BMW 1100RT coil is allowing the coil to spark with the spark plug wires not grounded or not hooked to a spark plug. (with no load on the spark plug wires the coil can spark internally between the windings or between the windings & the coil case)

 

If you have the early (gray) coil those are a little more fragile than the later coils.

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Time to step back and survey the battlefield again.

- Had "handle heater" wires mistakenly plugged into front brake switch, several resulting symptoms (see OP). Bike ran around the block OK.

- Corrected that and examined all wires under front cowling.

- New splice tape wrap everything in front of gas tank.

- Bike started and ran at idle / low revs on centre stand, OP symptoms not in evidence = no drama.

- Next morning, attempt to start but no joy.

- No spark seen at plugs when removed from cylinder and grounded to body.

- Several tests as DR recommended.

- Open circuit found on ignition coil secondary, awaiting replacement coil and GS911 diagnostic tool.

 

I could have fried the coil checking for spark as DR explains - don't think so, but possible.

 

The cause of no spark / no start is not yet confirmed - i.e. it could still be something other than coil.

 

Electricity is fun.

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  • 4 weeks later...

Bike has a short - so does my brain evidently. All help appreciated.

Summer is passing me by and I can't ride.

Update on the '97 RT with no sparky condition.

 

Wiring checked pretty closely everywhere by this carpenter (i.e. may very well be something I am ignorant about). Previously as reported above bike started and ran, then next day no sparky.

Found "open circuit" condition on secondary ignition coil.

Replaced coil.

Bike started yesterday and ran awesome on 30 minute test drive. Happy happy.

Only issue was ABS lights flashed alternately on 1/2 second interval.

Back in shop I "reset" the ABS according to instructions found somewhere….

Ground middle terminal of diagnostic plug.

Turn on ignition, hold ABS switch for 8 seconds.

Got both ABS lights staying on, turn off ignition.

End of day so I did not start bike again after this reset.

This morning ====== NO SPARKY AGAIN, WTF!!!!!?????????!!!!!!!!!!

Did my ABS reset somehow trip something else?

Ran like an absolute champ last evening before the reset.

 

Moved gas tank back and checked ignition - all good with 7.8k ohms impedance across secondary.

(Spec calls for 15k, part I have is new and reading has been consistent.)

 

Plugs are good, cables are good, switches are all good.

With key on I get dash lights; battery is good and starter cranks fine.

Can anyone please tell me what I am missing??

Thanks in advance,

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Evening Randy

 

Did you check for 12v at the coil green power wire with key on?

 

Your coil secondary resistance is probably OK--there are 2 values-- the early coils were about 13 ohms & the later coils are around 7 ohms.

 

If you have 12v to the coil (key on or engine cranking) then your problem is probably on the control (Motronic) side. Like a Motronic issue, or HES issue, or Motronic power issue.

 

You might try removing fuse 5 for about 5 minutes then reinstall & re-try starting.

 

If nothing obvious then you are going to have to go over every control circuit & Motronic input one by one until you find the problem.

 

Does fuel pump run for a couple of seconds at key on & run during engine cranking?

 

Is you battery voltage staying over 10v during engine cranking?--try using jumper cables from your car or truck.

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Ok, big clue.

I do NOT get 12v at coil green wire with key on.

Where does that lead me?

Looking at the kill switch now.

 

Other - what is the "Load-relief relay" listed on page 8-5 of Haynes manual?

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Battery stays on trickle, good 12.8v always.

I do NOT have 12v at coil green wire with key on.

I did try the 8+ second reset of Fuse 5 and no change = no spark.

I have 12v into Fuse 5 with key on.

I have 12v into port 30 of Starter Relay with key on.

I have Neutral light on dash with key on.

I hear clicking with key on in time with both ABS lights flashing simultaneously.

I have right grip switches apart and in pieces now - no obvious problem except dirty. (Lots of little parts, eh?)

I do NOT have head light at the moment (with right switches apart), but did have it earlier with no spark.

 

Can just part of Starter Relay fail?

Can I get this Relay at local auto parts store, or BMW only?

 

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I do NOT have 12v at coil green wire with key on. (you need 12v there for engine to start & run)

I did try the 8+ second reset of Fuse 5 and no change = no spark. (OK)

I have 12v into Fuse 5 with key on. (that's good)

I have 12v into port 30 of Starter Relay with key on. (again good)

I have Neutral light on dash with key on. (good)

I hear clicking with key on in time with both ABS lights flashing simultaneously. (normal)

I have right grip switches apart and in pieces now - no obvious problem except dirty. (Lots of little parts, eh?)

I do NOT have head light at the moment (with right switches apart), but did have it earlier with no spark. (good sign)

 

Can just part of Starter Relay fail? (anything is possible but not likely)

Can I get this Relay at local auto parts store, or BMW only? (maybe)

 

Morning TimberGuy

 

The coil (green wire) is powered directly from the ignition switch (no fuse). There is a splice in the main wire harness where a lot of green wires come together, one of those green wires goes on to the ign coil, one goes to fuse #1 & one goes on to fuse #7.

 

SO-- with key on do you have 12v to fuse #1 & fuse #7?

If "YES" then your problem is probably in the green wire between splice & the ign coil. IF "NO 12v" to fuse 1 & 7 then look for a broken green wire coming out of the ignition switch (usually at or near the first zip tie)

 

BOTTOM LINE HERE-- you need 12v to green wire of ign coil for engine to start & run.

 

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I can just feel a solution close at hand. Maybe not unobtainium, but I am not dancing yet. I have taken right grip apart and cleaned / evaluated all switches, nothing mechanically interesting found.

 

Current status with key on:

- 12v at coil green wire

- 12v at Fuses 1,5 & 7

- dash lights including Neutral, ABS both flashing, battery

- head light on

- clock on, BUT NO OTHER RID INFO

- 12v to one lead on the right hand kill switch

 

Nothing happens when ignition button depressed, no starter action.

Note that RID has no signals other than clock.

No voltage on either lead for round green ignition button.

I think there should be something on wire from RID to start button (blk/yel ?).

 

Fuel level brown wire shows solid connection with ground, zero ohms.

 

My troubles keep jumping around which puzzles me, but in patient mechanic fashion I am more curious than frustrated wanting to understand how it all works.

 

So what do I trace to get RID to work with key on?

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So what do I trace to get RID to work with key on?

 

Morning TimberGuy

 

On your RID operation-- 12v comes out of ign switch,, then through the kill switch,, then through the SIDE STAND switch,, then on to the RID.

 

SO -make sure the side stand is UP & the side stand switch is working correctly. Or just bypass the side stand switch by connecting (or jumpering) the wires together.

 

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I've got 12v to my kill switch which means ignition (key) is Ok.

 

Should there be 12v to one side of the starter switch button (the two little taps that are joined when button is depressed)? Elec current flows to starter button FROM the RID (which comes from Side Stand coming from Kill Switch? (Starter button presumably feeds starter directly.)

 

I have the Side Stand wires nutted together about 4" from main harness under the seat. At key on I should measure 12v between that point and battery ground terminal - I remember that was NOT the case. I should also be able to measure continuity (zero ohms with Kill "engaged") between Kill switch and Side Stand nut, and this should show 12v with Kill in neutral position.

 

Looks like a break in the line from Kill to Side Stand, any common failure point along that route?

 

Sure learning a lot about this bike!

Sending you PM as well but please keep technical stuff here for archiving.

 

 

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Afternoon TimberGuy]

 

I've got 12v to my kill switch which means ignition (key) is Ok. (good)

 

Should there be 12v to one side of the starter switch button (the two little taps that are joined when button is depressed)? Elec current flows to starter button FROM the RID (which comes from Side Stand coming from Kill Switch? (12v power DOESN'T come from RID as RID has no internal battery & no way to switch battery power even if it did.

 

Power flow =__ ign switch_to_kill switch_to_side stand switch_to_ starter button_to_starter relay).

 

(Starter button presumably feeds starter directly.) (NO, starter button activates starter RELAY & that (starter relay) in turn uses BATTERY power to energize starter solenoid).

 

I have the Side Stand wires nutted together about 4" from main harness under the seat. At key on I should measure 12v between that point and battery ground terminal - I remember that was NOT the case. I should also be able to measure continuity (zero ohms with Kill "engaged") between Kill switch and Side Stand nut, and this should show 12v with Kill in neutral position.

 

Looks like a break in the line from Kill to Side Stand, any common failure point along that route? (yes, those darn wire nuts, so start looking there)

 

 

 

 

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I find Green/Red wire at Side Stand is damaged back to main harness - looking further now but it is messy. Below assumes I find no damage to any other wires but Green/Red.

Green/Yel seems to be better.

Opening up the right grip again to test for continuity, etc between Kill and Side Stand.

I get continuity between Green/Red of Kill and Green/Red of Side Stand, but when energized with key on I do NOT get 12v at Green/Red of Side Stand. Why does this not blow a fuse?

Tells me it is shorted somewhere.

Green/Yel shows zero ohms between Starter Button and Side Stand.

Elec flow is FROM Side Stand to Starter Button, no flow INTO Side Stand so no flow to Starter Button.

 

Conclude Green/Red wire is bad between Kill and Side Stand?

 

Can I just bypass the whole Side Stand circuit and jump from Green/Red off Kill switch directly to Green/Yel of Starter Button (cut Green/Red)? (Assuming no short in Green/Yel anywhere, must NOT cut Green/Yel because it connects to RID and Motronic Relay.)

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Can I just bypass the whole Side Stand circuit and jump from Green/Red off Kill switch directly to Green/Yel of Starter Button (cut Green/Red)? (Assuming no short in Green/Yel anywhere, must NOT cut Green/Yel because it connects to RID and Motronic Relay.)

 

 

Afternoon TimberGuy

 

Yes, you can jumper Green/Red coming out of kill switch directly over to Green/Yellow going into start button completely bypassing the side stand switch. That should allow engine cranking

 

BUT!-- that by-pass will then not power up the RID so you will need to find a way to get key-on 12v into the Green/Yellow wire going to the RID.

 

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Wow - what an exercise!

 

I found Grn/Red wire near Side Stand partially melted to a plastic wrap on main harness beside air box, looks like an old condition that I exacerbated with my handling. Had shorted wires together long ago to bypass Side Stand.

 

At the right grip, I jumpered Grn/Red from Kill to Grn/Yel of Starter Button which seems to work OK and still runs the RID. Leaves two loose ends at Side Stand - one is dead and cut at right grip, the other (Grn/Yel) is open 12v potential at key on. Will just cap it because it also attached to RID and Motronic and Fuel Pump Relay.

 

So now at key on I seem to have good most everywhere - EXCEPT no 12v at Injector Green wires.

What I DO have at KEY ON is:

- Headlight on

- N light on dash, with battery and oil illuminated

- 2 ABS lights flashing together at 0.5 sec on / 0.5 sec off

- RID is on

- 12v at coil green wire

- Starter turns

- 12v at Fuse 5, all fuses good

 

I have pulled Fuse 5 for a minute (reset) and still NO 12v at injectors.

Battery is good, remains on trickle full time.

I hear fuel pump run shortly with key on.

Fuel Pump Relay shows 12v at 2 different terminals, and I've swapped it with another without change.

 

Specific Q's:

1) What to check next to get 12v at injectors?

2) What is CO Potentiometer? Those wires open and unused on this bike, no mention in manuals just on E diagram.

3) What does it feel like to ride a motorbike? Been so long I forget.

 

{DR - sent you a PM}

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Afternoon TimberGuy

 

Start at fuse #6 --that supplies 12v to fuel pump relay power termainl.

 

If OK there then your problem is probably back at the side stand switch as the green/yellow wire is what supplies 12v power TO the fuel pump relay PULL-IN coil.

 

In any case you will have to find a way to provide 12v power to the fuel pump relay pull-in coil (that goes in via the green/yellow wire.

 

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Update - I do get 12v at injectors during the short start with key on.

13.3 v into Fuse 6.

 

Digesting your note now.

 

OOPS - embarrassed. I just found coil connector undone after checking voltage there. Hopeful. Need to trickle battery a few minutes and then will try starting again.

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More TimberGuy

 

Specific Q's:

1) What to check next to get 12v at injectors? (see post above) --also Motronic controls fuel pump relay & therefore injector green wire

 

2) What is CO Potentiometer? Those wires open and unused on this bike, no mention in manuals just on E diagram. (Co pot is only used on European/English bikes to control idle fueling) --basically is used to set idle Co when no CCP is used

 

3) What does it feel like to ride a motorbike? Been so long I forget.

--(Can't help you here as I have many motor bikes so at least one is always able & ready)

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The merry-go-round has almost reached back to starting point.

Current status = crank but not spark.

Have removed left side spark plug and grounded to look while cranking, no joy.

I have pulled Fuse 5 for a minute to reset, no joy.

Quoting DR's first response with what I am finding now.

 

Have you checked for (key-on) 12v to the ign coil green wire? If not then start there.

YES - HAVE 12V THERE.

 

If 12v to the coil then check fuse #5 for continuity as well as power to & through fuse #5.

FUSE 5 GOOD

 

Does headlight come on at key on then go off during engine cranking?

YES AND YES

 

Do you have (key-on) 12v power to the green wires at the fuel injectors?

YES FOR SHORT TERM AT KEY ON AND MULTI-METER BOUNCES DURING CRANKING

 

Do you have (key on) 12v power to the 86 terminal of the motronic relay? (in fuse box)

ONE TERMINAL HAS CONSTANT 12V, OTHER GOES 12V AT KEY ON.

 

BATT SEEMS SOLID ON CONSTANT TRICKLE, ABLE TO CRANK SEVERAL SECONDS.

 

Do the above verifications then we might have a direction to take from there based on what you find or don't find.

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Afternoon TimberGuy]

 

Have you checked for (key-on) 12v to the ign coil green wire? If not then start there.

YES - HAVE 12V THERE. good

 

If 12v to the coil then check fuse #5 for continuity as well as power to & through fuse #5.

FUSE 5 GOOD good

 

Does headlight come on at key on then go off during engine cranking?

YES AND YES good

 

Do you have (key-on) 12v power to the green wires at the fuel injectors?

YES FOR SHORT TERM AT KEY ON AND MULTI-METER BOUNCES DURING CRANKING (not good you need constant 12v during cranking--what is your battery voltage during engine cranking?)

--OR you have resistance in the green injector circuit

 

Do you have (key on) 12v power to the 86 terminal of the motronic relay? (in fuse box)

ONE TERMINAL HAS CONSTANT 12V, OTHER GOES 12V AT KEY ON. good

 

BATT SEEMS SOLID ON CONSTANT TRICKLE, ABLE TO CRANK SEVERAL SECONDS. (what is your battery voltage during engine cranking?)

 

 

 

 

 

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Dig meter says 12.5v before cranking, drops to 11.2v during cranking and then returns to 12.4v.

Does NOT crank well, nor for long - only a couple turn overs achieved now.

I've been testing so often and for so long that I worry trickle is not keeping up.

It is an Odyssey battery and has worked very well recently.

No hint of sparkage.

Should I cool my jets and trickle overnight before next?

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Dig meter says 12.5v before cranking, drops to 11.2v during cranking and then returns to 12.4v.

Does NOT crank well, nor for long - only a couple turn overs achieved now.

I've been testing so often and for so long that I worry trickle is not keeping up.

It is an Odyssey battery and has worked very well recently.

No hint of sparkage.

Should I cool my jets and trickle overnight before next?

 

Evening TimberGuy

 

That 11.2v cranking is very good so your battery is supplying enough to run the ignition during cranking.

 

That jumping voltage on the green injector wire is still troublesome-- That sort of points to some sort of resistance in that current supply (that also supplies the fuel pump relay)

 

What is your present voltage on the green coil supply wire while cranking?

 

Added: On the overnight battery charge--YES, that is always a good thing as FULL cranking power is always a plus in engine starting.

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Still no sparky after all night on trickle.

I have 11.0v at coil green wire during cranking, repeated 3 cranking attempts.

Some command signal is missing to say "fire".

I can't believe HES has all of a sudden ALSO given up the ghost - in addition to all the other elements I've fixed / corrected - but of course this is technically possible.

 

I have a GS-911 sitting here but don't see any ability to diagnose anything with it until running.

Any ideas?

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Afternoon Timber guy

 

Re-verify fuse #5 & #6, then verify 12v INTO & OUT of fuse 5 & 6.

 

Check red wire going into Motronic for 12v.

 

Check green/black wire going into Motronic for 12v with key on.

 

Make sure you hear fuel pump run for a couple of seconds at key on & pump runs during engine cranking.

 

My gut feeling is that you are low on voltage on the Green/Yellow wire going into the fuel pump & Moronic relay. (that is fed by the power into & out of the side stand switch & I'm not sure you have that CIRCUIT by-passed correctly).

 

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I appreciate your suspicion since that is the 'most odd' thing I've done with wiring here. Green/Yellow wire was cut at Side Stand and open - I read good 12v there with key on. Green/Red from Kill switch is now a dead wire with both ends unattached, stub at right grip soldered to Green/Yellow terminal of Starter button. Found a tiny bit of damage to Green/Yellow when I traced them back to main harness, cut that out to existing open end.

 

Fuse 5 & 6 both read zero ohms resistance.

With key on both read 12.4 v at rear socket (battery reading 12.4v).

 

Motronic connector does not seem to correspond with any of the manuals or diagram resources I have (I've never opened this connector before).

I have 15 wires in/out Motronic not counting 2 brown ground to mount:

socket #1 - Brown (heavier wire)

socket #2 - Brown (heavier wire)

#5 - Red / Black

#8 - Red / Blue

#9 - Brown

#12 - Clear

#13 - Clear

#14 - Red (heavier wire), power lead

#15 - Green

#18 - White / Black

#19 - Yellow / Red

#20 - Brown

#21 - Black

#24 - Red

#25 - Green

 

Red wire at socket #14 is constant 12v (same reading as battery) with key on or off.

 

At key on I get 12v at:

#5 - Red / Black

#14 - Red

#15 - Green

#18 - White / Black

(all the others register a small, milli, voltage that I have not yet recorded)

 

I cannot see the wire colours in/out of relays without some extra effort.

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Evening TimberGuy

 

This is getting more & more difficult as we eliminate things.

 

Power to the Motronic seems good so it sounds like wiring is in order as long as you have 12v to injectors & ign coil with key on.

 

Try turning the crankshaft slowly on the front pulley nut & see if you get the fuel pump to cycle as the HES triggers.

 

 

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I do NOT hear any fuel pump cycling with slow crank turn from front end.

I do hear a short fuel pump run at key on.

Sure seems like the electronic gremlin remains one step ahead of me.

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Evening TimberGuy

 

I do NOT hear any fuel pump cycling with slow crank turn from front end.-- This usually points to a failed HES or something in the wires or connector between the HES & the Motronic

 

I do hear a short fuel pump run at key on. -- This usually means the Motronic is powered up & capable of triggering the fuel pump relay.

 

You are getting into a trouble shooting area that is difficult without known good parts to try on the engine.

 

Usually the HES is the cause BUT with what we know now bad wire connections or a failed Motronic can't be ruled out.

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If I understand it correctly - the HES sends out a signal with every revolution that "bumps" the fuel pump to keep up fuel pressure. A little bit of pumping with key on primes the system that is then maintained with cyclic additional pumping. The initial priming is not enough to start the motor - or more likely the HES signal triggers other functions in Motronic to send spark signal. Interesting that cycling the fuel pump like that doesn't create more problems.

 

Can I confirm fuel pump operation with 12v to specific leads at connector (and grounded of course)?

 

I'll do the test again to confirm = key on, slow crank of front pulley listening to fuel tank right side for fuel pump to engage. Presumably it will run as long as HES in sweet spot.

 

Is there any other test that can be done to confirm a failed HES - i.e. read a terminal in the Motronic connector with similar slow rotation of crank? I cleaned all the HES lines and connector during rebuild, would be surprised at problem there but will look if possible.

Maybe Greiffster was right out of the gate - we'll see.

 

Did I read somewhere that Hall sensors can be found at a good generic auto parts store sometimes? Of is that straight from BMW dealer shop? Fellow in Vancouver adverts to rebuild them - will look him up.

 

Overall situation could be consistent with failed HES - be it highly coincidental. Good test ride, put up for the night. Next morning no spark. The weird part is that ignition coil seemed to have died exactly the same time. Are those two connected in any way?

 

Sounds like next step is to eliminate HES as weak link - get a new one installed.

 

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The HES would be my first port of call because we KNOW this item (mainly the loom attached to the actual sensor) is a real problem area.

Get this replaced and start from a point of confidence there.

So, it is unlikely to be the actual sensors, but the leads. The complete unit can be bought from http://www.euromotoelectrics.com/BOSCH-Hall-Effect-Sensor-R1100-12-11-2-306-137-p/boignsen-r137.htm

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Morning TimberGuy

 

I have very limited time for a response this morning so this will be short & not very detailied--

 

If I understand it correctly - the HES sends out a signal with every revolution that "bumps" the fuel pump to keep up fuel pressure. A little bit of pumping with key on primes the system that is then maintained with cyclic additional pumping. The initial priming is not enough to start the motor - or more likely the HES signal triggers other functions in Motronic to send spark signal. --Pretty close-- the HES has two actual hall sensors on the mounting plate (TDC & BDC) one sensor controls spark & one fuel. As a rule the SENSORS THEMSELFS never fail it is the wiring to & from the sensor that fails (usually JUST above the actual sensor). The wires don't break but the insulation degrades & cracks so the wiring signal cross-talks to the other wires & that confuses the Motronic with strange signals or no usable signals.

 

Can I confirm fuel pump operation with 12v to specific leads at connector (and grounded of course)? -- Yes, just put a 12v test light across the fuel pump (+) & (-) wires at the fuel pump connector.

 

I'll do the test again to confirm = key on, slow crank of front pulley listening to fuel tank right side for fuel pump to engage. Presumably it will run as long as HES in sweet spot. (might work)

 

Is there any other test that can be done to confirm a failed HES - i.e. read a terminal in the Motronic connector with similar slow rotation of crank? I cleaned all the HES lines and connector during rebuild, would be surprised at problem there but will look if possible. --You can build an HES tester but those are usually not reliable in finding signal cross-talk issues due to cracked wiring or insulation issues.

 

Did I read somewhere that Hall sensors can be found at a good generic auto parts store sometimes? Of is that straight from BMW dealer shop? Fellow in Vancouver adverts to rebuild them - will look him up.-- I haven't ever seen one that will work at an auto parts store.

 

Overall situation could be consistent with failed HES - be it highly coincidental. Good test ride, put up for the night. Next morning no spark. The weird part is that ignition coil seemed to have died exactly the same time. Are those two connected in any way? -- No real connection other than the HES tells the Motronic to fire the coil. Your failure seemed to be on the 12v side anyhow & that has no tie-in to the Motronic or HES directly.

 

Sounds like next step is to eliminate HES as weak link - get a new one installed. --Yes, OR cut your existing HES wire harness open just above the HES plate & look for cracked/degraded insulation on the wires.

 

 

It is also possible that your 12v circuit to the coil originally failed & your working on the HES wires/connector moved the wires enough to cause the HES issue. (if you cut the harness insulation open & find cracked/degraded insulation you have probably found your no sparky, no fuel pump during crank issue)-- or at least it needed to be repaired anyhow no matter what else is wrong.

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If I understand it correctly - the HES sends out a signal with every revolution that "bumps" the fuel pump to keep up fuel pressure. A little bit of pumping with key on primes the system that is then maintained with cyclic additional pumping.

 

HES sends the signal which is evaluated by the Motronic which triggers the signal to the pump relay (among other things). There is no "bumping". MOtronic expects to see the engine turning signal (from HES) every so often. If this signal is not "seen" for a certain period of time, there is no actuation signal to the relay and the fuel pump doesn't run. This is a safety feature to make sure fuel pump doesn't run in case of an accident (engine stopped, ignition still on). Otherwise, the pump runs constantly and the pressure regulator maintains the pressure. Initial priming is done every time the ignition switch is turned without looking at the HES.

Basically if the HES is not sending the "turning" signal, Motronic is sitting there thinking "I would do what I need to do if only the engine would start spinning".

 

You can test the pump just like any regular motor.

 

 

 

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I've got the HES out and en route to GSAddict for rebuild - he lives just across the Strait from me. Will report back soon.

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Fair Q.

Fellow that rebuilds them is close by and comes well regarded in local riding circle - fast, fair, competent. His pre-work service by email is encouraging. I like supporting local talent and energy when I can, as I wish to be respected for my skills rather than discounted because I am not "cheapest" nor shiny new.

I have questions about OEM components - do they still have the same "issue" that everyone has known about for years, or not? I don't have enough info about that to make an opinion, but lean toward my cautious view of the world.

 

Price is a concern. North of the border cost for new BMW part is $450 CAD plus shipping and supply time is often a couple of weeks.

Euro part listed for $230 USD which is $290 Canadian plus shipping & a duty at the border.

Rebuild is about $125 plus shipping two ways ($50 with insurance) = easily half any other option.

If I bought all new parts for this 1997 bike I would have many grand in the rebuild, instead I've got less than "a couple" grand in it because I used generic parts when I thought appropriate and splurged for new when I had to.

Turn around time is about the same I hope - week or two and I live relatively remote.

If the repair isn't done well I'll hop in the truck and go visit the guy at his house until issue resolved fairly.

 

Add to that my philosophy of the project. This is a 1997 R1100RT with 165,000 miles on odo.

I am not looking for the ultimate performance machine, but I will have a very reliable bike that I can hop on and head to Halifax (as soon as I evict the elect gremlin I've got) with confidence. (Even more confidence than a new bike right off the showroom floor.)

FOR ME - newer most of the time does not mean better (keep hoping the wife doesn't want to trade me in for a newer, more sporty model).

I like understanding how this bike works and knowing I can fix almost all of it myself. Haven't heard anyone say that they can do that with a new RT.

 

Sorry about the little soapbox. I watch the news every now and then and am reminded that much of the world is pretty screwed up and dysfunctional - as much in "developed" societies as those in crisis. Mrs and I have created the life we want and work to make the world better locally.

 

Thinking thru it all again - I'd make the same decision again tomorrow.

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Thanks for the explanation, bro. Couldn't agree with you more. And I bet many on this forum feel the same way about searching for parts & working on their bikes.

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GS Addict will do a great job rebuilding it for you. You have no worries.

 

Well that is reassuring.

I was concerned because I know of cases where a 'competent friend' has rebuilt these and just used normally insulated cables.

I just want the best outcome for TimberGuy.

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Good evening Randy

 

I have been giving some thought to getting the HES rebuilt as well, does GS Addict take orders or just for friends.

 

Ron in Calgary

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GSAddict sent me a note saying my HES unit was "as bad as it gets".

We don't know if this is an original HES unit or replacement - 165K miles on the bike.

He has fixed it and will ship to me tomorrow.

 

I think he likes the work so send him a PM (Personal Message) via this site, or at his email address listed in Profile.

He will test it before opening anything to confirm operation / not.

 

Watch this space early next week for a report on Test ride #3, I have a lot of riding to do and luckily our season can be 11 months most years.

Thanks for all the help to date.

 

DR - how about that PM I sent to you recently?

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Happy to report that I am rolling again and looking forward to catching up on 2015 kilometerage. Installed rebuilt HES last evening and Marlene started up straight away. Test run all good so today I'll dress her in tupperware and wash her for the maiden run with Mrs. Timber this evening.

 

GSAddict offered a quick turn on the HES repair and I'm happy to recommend him in all respects. He thinks my HES "might" be original - recall that the bike has 165K miles on it. Doc (previous owner) might know better. HES was in BAD shape and could have left me stranded anywhere anytime. All my poking, prodding, and pulling of wires probably accelerated the failure.

 

Marlene's rebuild has been great fun for me - I'll summarize the project on the other thread to make it complete.

 

Many thanks to all contributors - you made it safe for me to disclose my ignorance and mistakes. This is a great resource for Marlene's care and I look forward to paying it forward as well.

 

Randy

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