Won't start

[BrianP]

Hello from Scotland. I've a '96 1100rt that I've been riding for four years with little trouble. Now it won't start. Doesn't turn over.

 

Symptoms almost like side stand down except, switch on ignition and get the 3 second hum you'd expect to hear (don't get that if the side stand's down or kill switch is on). Press starter and starter relay clicks, so starter button ok. Ignition/Neutral lights don't dim when the button's pushed, suggesting no load from the starter. I've stripped and cleaned the starter.

 

I'd be grateful for any ideas.

[dirtrider]

Morning Brian

 

You might have a bad starter relay, or broken wire at the steering neck area, or even a low enough battery that it can't pull the starter solenoid plunger in.

 

 

First, make darn sure the trans in neutral-- then try jumping the large battery cable stud on the starter to the smaller solenoid stud on the starter.

 

If it then cranks over OK let us know & we can have you trouble shoot the starter circuits from the starter relay socket (left front relay in the fuse box).

 

If it still doesn’t crank by jumping the solenoid then look for a low battery, or starter issue, or battery cable connection issue.

 

[scotboxer]

Hi

 

And happy St Andrew's Day from a fellow Scot.

 

Battery? It is that time of year when they die!

 

I would also check the wiring around the ignition switch. I had an RS with an infuriating intermittent fault and that's what it was. Try moving the handlebars around when ignition is on and see what you get.

[BrianP]

Thanks for that. I'll try jumping the starter as you suggest. The battery should be ok - it was new six months ago and I've tried jumping it with a car battery. The starter relay is clicking, but maybe that doesn't mean it's ok on the output side. I'll be very happy if that's all the problem is!

 

It's only 5.30 pm here but it's pitch dark, so maybe have to leave it til the morning.

 

[BrianP]

We're everywhere!

 

Battery should be good and I've tried jumping it with a car battery. Doesn't seem to an intermittent fault, but not ruling out anything! I'll check the wiring round the switch, although lights are all normal and power's getting to the starter relay.

 

[BrianP]

Hi. Crossed the starter as you suggested and it cranked just fine.

[dirtrider]

Afternoon Brian

 

If the starter relay is clicking AND you can get the starter to crank the engine by jumping at the solenoid--

 

Remove the starter relay & turn it over-- there should be some numbers next to the terminals on the bottom (like 30,86a,87,85)

 

So, first thing to check is that terminal 30 in the relay socket has 12v power to it (if not then check the small red wire connection to battery + post).

 

If 30 OK with 12v power-- next, use a jumper wire to jump 30 to terminal 87. That should make the starter crank.

 

If the relay is clicking when you push the starter button then 85,86,86a should be OK.

 

If it cranks when you jump 30 to 87 then more than likely a bad starter relay or the relay socket is corroded & oxidized.

 

[BrianP]

Getting 12v to terminal 30. Put a jumper between 30 and 87. Nothing.

[dirtrider]

Afternoon Brian

 

 

 

OK, there is black wire that runs from terminal 87 in the fuse box to the small terminal on the starter solenoid.

 

More than likely that black wire is either broken between the relay socket & the starter, or one end or the other has a bad connection to the terminal crimped on the ends.

 

You might try putting that jumper in between 87 & 30 then wiggling the black wire at both ends to see if you can find bad connection.

 

Also, VERIFY that the12v power TO terminal 30 stays at around 12v when you jump 87 to 30 (possibly the terminal 30 power feed wire has a high resistance connection to the battery & goes low when you put a load on it)

 

[BrianP]

Good morning Dirtrider

 

12 plus volts on terminal 30. Put the jumper across to 87 and the volts didn't just drop - they disappeared altogether. Did it again and again with the same result (in case I hadn't put the jumper right home in 30). With the jumper in 30 there's 12v at the other end of the jumper and as soon as I push it in to 87, no volts. No obvious signs of a load - ignition lights don't dim. I don't understand how that can be.

[dirtrider]

Morning Brian

 

That 30 circuit FEEDS off the (+) post at the battery, there is a good possibility that the small red wire hooked to the battery (+) post has come loose or is heavily oxidized.

 

At least start you looking there.

 

Otherwise a high resistance area in that red 30 power feed wire or one of it's connections.

 

[BrianP]

Wires to the positive terminal on the battery look good, but I cleaned them up. No difference. The 30 terminal is getting the feed ok. I don't understand how the feed vanishes as if it was never there when I put the loop in. It's not that the feed's not getting from 87 to the starter. It's just plain not there as soon as I put the loop in. It's as if 87 is activating a switch that turns the feed off.

[dirtrider]

Wires to the positive terminal on the battery look good, but I cleaned them up. No difference. The 30 terminal is getting the feed ok. I don't understand how the feed vanishes as if it was never there when I put the loop in. It's not that the feed's not getting from 87 to the starter. It's just plain not there as soon as I put the loop in. It's as if 87 is activating a switch that turns the feed off.

 

Afternoon Brian

 

I just looked in my BMW wire diagrams & that red wire coming off the battery (+) post has a solder joint where it branches off to also feed the ignition switch.

 

If you don't lose other ignition switch functions then your problem is more than likely in that solder joint or in the red wire between that solder joint & the 30 terminal in the starter relay socket.

 

I really don't know what to tell you other than that solder joint would be a pain to find without unwrapping the main wire harness.

 

I think if it was me I would run a new wire directly from the battery (+) post to the 30 terminal in the starter relay socket.

 

The only reason I can see that you are losing power in that 30 cavity when you hook it to the 87 is due to high resistance in that 30 circuit wire (or a connection).

 

You ARE testing for 12v power in the 30 socket with your meter or test light hooked to GROUND aren't you? (not between the 30 & 87).

 

[BrianP]

Yes. Meter negative to frame and positive in 30 - 12v plus. put the loop in and meter neg to frame and positive in 30 - 0v! Loop out and 12v back again.

 

You'd think if there was a dry solder joint or a poor connection the problem would be intermittent or show up with a bit of wiggling, but that's not happening.

 

The immobilizer was bypassed by the previous owner and I wonder if a gremlin has appeared as a result of that?

 

Could I run a new wire from 87 direct to the starter solenoid?

[dirtrider]

Afternoon Brian

 

On the immobilizer?-- That is a thought. I wonder where that interrupts the starter signal? An immobilizer isn't common on the 1100 here in the US, that is more of a European insurance thing.

 

On running a wire directly to the 87 terminal?-- NO , that would keep the starter energized all the time. The ONLY time 87 is energized with 12v power is WHEN you want the starter to crank.

 

If you need a temporary repair you could run a wire from the 87 terminal to a momentary push button switch then run a wire from battery (+)post to that switch. Just push the button to crank engine (that is basically all that starter relay does).

 

A more permanent repair would be to access the bottom of the fuse box then run a wire from the battery B+ post directly to the 30 terminal in the starter relay socket. The original isn't fused but personally I would fuse that rogue wire on general principle.

 

[BrianP]

Thanks DR

 

Looks like access to the underside of the fuse box is a bit of a mission. Ill sleep on it and have another go tomorrow.

[dirtrider]

Afternoon Brian

 

 

Yes,the underside of the fuse box is a real bit*h to get to.

 

Maybe this schematic can assist you in some way.

 

[Jim Moore]

Looks like everyone in this conversation is smarter than me, but I'll throw in my two cents. Are you sure you pulled the starter relay and not the CCP? They sit right next to each other. Also, you're jumping hole 2 to hole 6 in the relay socket? With the key on? I've never seen that trick fail to start the bike.

 

Good luck,

[dirtrider]

Morning Jim

 

Good point, sometimes we can overlook the obvious.

 

[BrianP]

Hi Jim

 

Yes, definitely the starter relay. The thing that has me baffled is that I'm getting 12v plus at 30 (6) but as soon as I put the loop in to 87 (2) the supply disappears from 30.

[BrianP]

Hello DR

 

Thanks for the schematic.

 

Since I'm getting supply to 30 do you think the problem might be between 87 and the starter? If that wire is broken or down to earth would that explain the disappearance of the supply when I put the loop in?

 

[dirtrider]

Morning Brian

 

Just to see what your are dealing with-- take a wire with a light bulb in the wire (in series).

 

Now hook one end of that wire to the battery (+) post.

 

Next, measure the voltage on the other (free) end of that wire with a voltmeter.

 

It will show 12v.

 

Now, ground the open end of that wire to the battery (-) post.

 

It will now show close to 0 volts & the light bulb should light up.

 

Your voltmeter or test light takes very little current to operate but once you put a high current load on that 30 circuit the load (starter solenoid pull in coil in this case ) that load trumps the resistance in the 30 wire circuit & drops it to close to 0 volts.

 

One more test you really should try just to verify that you have the correct relay terminals is to run a jumper wire from the battery (+) post then touch it to the starter relay 87 terminal in the relay socket. (see if the starter will then crank the engine)

 

[BrianP]

GOT IT!!

 

DR you were spot on. When the immobilizer was by-passed the junction that show on your schematic on the supply wire to 30 was twisted together and taped up ( he obviously didn't have crimp connectors, or just made a 'temporary' connection. the twists were too short and were coming undone under the tape. I joined it with a proper connector and the bike starts A1 again. Brilliant!

 

Many thanks for your help. If you're in Scotland anytime there's a bed and a bike here for you!

 

Thanks again.

 

[dirtrider]

GOT IT!!

 

 

Afternoon Brian

 

Wonderful, glad you got it sorted.