Anyone help decipher powerscreen wiring 1995 RT?

[IrishBob]

Hi all. Got directed here from the good folks at BMWLT Forum as they think you might be able to help pin down the prob:

This is link to the discussion on their site (with pics) and all the progress so far. Hopefully we can get this sorted and back on the road asap:

Basically 1995 R1100RT power screen not working but all elects/switches are checking out OK!

https://www.bmwlt.com/forums/rt-series/182617-anyone-help-decipher-powerscreen-wiring-1995-rt.html#post1907469

[AndyS]

So far:

You have fitted 2 new relays.

You have confirmed the motor works (by powering it up seperately from the bike).

You have established you have power from handlebar switch 12v ok for both up and down,

You have got earths on both replays and the motor ok.

You have grounded the up/down switch from the relays (not the handlebar) to the up/down switch on motor.

The screen relays do not click when handlebar switch is depressed however - there is 12v going into the relay coils terminal 86 and 12v coming out of terminal 85 when switch is pressed but the 30 terminals show nothing - these are the main feeds to motor.

You did a continuity test on the limit switch with common earth - result no continuity with either of the other 2 wires.

You Disconnected the 5 motor wires from the multiplug and checked the 3 on LS again - same result.
Then you went to main multiplug into which the 2 relays are located and performed following tests on connections under the relays. Results as follows:
        Mains feed to both relays (and using the multiplugs 2 earth wires to check) No87 at 12v
        Press handlebar switch (same test to both relays for up/down) Nos 86 & 85 both showing 12v but no click in relay
       Double check earth No 87a in multiplugs with a 2ndary 12v feed and both ok
       Neither the Blue or Purple feeds to the motor No: 30 are showing any power
       Relays will only click if earthed separately via 86/85 (different positions on up/down relays)(and subsequently power the motor if reconnected.

 

Then you shorted all 3 wires at the limit switches - the handlebar switch works both ways.
You pulled the motor and removed the micro switch. Using multi meter you tested for continuity over the 3 terminals using earth as common but no continuity signal through the other 2. In turn pressed the up/down buttons (You say there are 2 tiny buttons on the switch 1 on top of the other) and both ping continuity ok tested.

 

Screen wiring diagram: https://ibb.co/GTChwDK

[dirtrider]

11 hours ago, IrishBob said:

Hi all. Got directed here from the good folks at BMWLT Forum as they think you might be able to help pin down the prob:

This is link to the discussion on their site (with pics) and all the progress so far. Hopefully we can get this sorted and back on the road asap:

Basically 1995 R1100RT power screen not working but all elects/switches are checking out OK!

https://www.bmwlt.com/forums/rt-series/182617-anyone-help-decipher-powerscreen-wiring-1995-rt.html#post1907469

 

Afternoon Bob

 

I didn’t go through the entire thread so this will be starting from scratch so will probably cover things that you have already done.

 

Don’t guess at testing, either do it as requested or answer that you didn’t do it  but don't guess.

 

Should be pretty easy to find the problem area___

 

Get a 12v test light as that is easier & quicker than a voltmeter. 

 

Now start from (A)  & work through as tests are added.

 

Test light clip on battery (EEE), probe at (A) of relay RAISE (light should be lit), then push  up button on handlebar (does light stay lit brightly?) yes/no

 

Test light clip on battery (EEE), probe at (A) of relay LOWER (light should be lit), then push  down button on handlebar (does light stay lit brightly?)  yes/no

 

Test light clip on battery (EEE), probe at (C) of  RAISE relay then push  ‘up’ button on handlebar (does test light light up  brightly at button push?) yes/no

Test light clip on battery (EEE), probe at (C) of  LOWER relay then push  ‘down’ button on handlebar (does test light light  brightly at button push?) yes/no

 

Test light clip on battery (EEE), probe at (D) on RAISE relay, then push up button (does light stay out or come on dim?

 

Test light clip on battery (EEE), probe at (D) on LOWER relay, then push down button (does light stay out or come on dim?

 

Test light clip on battery (EEE), probe at (E) on RAISE relay, then push up button (does light stay out or come on dim?

 

Test light clip on battery (EEE), probe at (E) on LOWER relay, then push down button (does light stay out or come on dim?

 

Test light clip on battery (EEE), probe at (J) on RAISE relay, then push up button, does light come on brightly-- yes/no 

 

Test light clip on battery (EEE), probe at (H) on LOWER relay, then push down button, does light come on brightly-- yes/no 

 

Test light clip on battery (EEE), probe at motor (Y), push up button, does light come on brightly? yes/no

 

Test light clip on battery (EEE), probe at motor (x), push down button, does light come on brightly? yes/no

 

Test light clip on motor  (Y), probe at motor (X) push up button, does light light? --yes/no

 

Test light clip on motor  (Y), probe at motor (X) push down button, does light light?-- yes/no

 

The above should be enough to get an idea of what to focus on, check back occasionally as I might add more if I think of something.  (If I add any I  will add those in RED font)

 

Test light clip on battery (Q), probe at (E) on each  relay  (is light lit?-- yes/no) 

 

When we get a root failure idea based on the above  testing then we can then define more local testing/evaluation.

 

[IrishBob]

Wow DR! That is a seriously professional and detailed reply and I very much appreciate you taking the time to do so.

Had a run through everything this morning as per your instructions and finally by fluke more than my skills have now determined that the blue limit switch is itermitantly faulty and hs now failed completely with 2 wires breaking off! Now the fun starts - as I cannot locate a new replacement switch even on Fleabay, it  looks like my next / only option is to buy a used motor assy from Fleabay - cost here about £40+.

I will keep in touch and let you know if the replacement resolves the problem.

[dirtrider]

1 hour ago, IrishBob said:

Wow DR! That is a seriously professional and detailed reply and I very much appreciate you taking the time to do so.

Had a run through everything this morning as per your instructions and finally by fluke more than my skills have now determined that the blue limit switch is itermitantly faulty and hs now failed completely with 2 wires breaking off! Now the fun starts - as I cannot locate a new replacement switch even on Fleabay, it  looks like my next / only option is to buy a used motor assy from Fleabay - cost here about £40+.

I will keep in touch and let you know if the replacement resolves the problem.

 

Morning Bob

 

Hopefully a new motor gets it going but I have some doubts as that green position switch by-pass that you added as a test should have removed both switches from having any effect as you effectively by-passed both switches  with that added grounding circuit.

 

 

[IrishBob]

Well folks finally got the replacement motor and fitted it today and...screen works perfectly. So not going to jinx this and say any more other than many many thanks to all who got in touch - you are stars.

[AndyS]

IrishBob, Nice to hear the conclusion.