Turn Signal issues, help!

[1991K100RS]

Hey Brickheads - help me trouble shoot a friends problem. He just bought a 1985 K100. His speedometer does not work, gear position indicator doesnt work, and when presses either turn signal, both continue to flash as if you pressed hazard light switch.

I cleaned-up the contacts of his transmission gear position indicator at the final drive, as well as where it connects near the radiator cover. Also pulled his flasher relay and cleaned it with contact cleaner; problem persists. Any ideas?

Thanks for your input in advance!

[wmax351]

Check the fuses. The horn/fan fuse goes out and causes the problems with the signals.


Does the odometer work? Check the cable that goes to the VR sensor in the final drive unit.

[johnny]

greetings 1991k100rs...

« on: december 06, 2013, 08:04:05 am » you wrote this...

Hey all, long time lurker - first time poster

I have a 1991 K100 RS with 60,000 miles, 10,000 of which are mine.

Went out for a ride yesterday and during the ride I noticed that the green light that illuminates the speedometer was flickering. When I tried to use my turn signals it flashed green real quick on the speedometer, then immediately stopped blinking. When I came to a stop, speedometer was completely dark with no light. As I throttled up, the light on the speedometer became brighter. By the time I arrived at my destination, I was riding with no headlight and a dark speedometer. Checked all the fuses, all looked good.

1 hour later, turned the key and the speedometer lit up, but no headlight. With key turned and ignition switch engaged all I hear is a single click sound (I believe starter solenoid). Turned the ignition back and forth a few times and one time light came on. I hit the ignition and it started up with headlight no problem. Have not been able to reproduce since.

I’m thinking the battery is not being charged by the alternator. Checked the alternator, and it’s plugged in…

Ideas;

1) Ground connection needs to be cleaned?
2) Starter brushes need to be cleaned or replaced?
3) Ignition switch contacts need to be cleaned?

Any thoughts on what could have been causing this pesky electrical problem?

and inge k wrote this...

If the background illumination in the cluster flickers/goes out, the LSR have a ground problem....clean starter commutator and/or change the starter brushes.

If also the warning lights in the cluster flickers/goes out at the same time, the problem is most probably the ignition switch.... which can be dismantled and cleaned.

Inge K.



so... what have you done... anything... either way the 1st thing i would do is eleminate a dirty starter by doing this...

put it in 2nd gear... key off... clutch in... roll it backwards... pop the clutch while rolling backwards... do that 5 times...

key on... is the headlight on... if so hit the start button... whats you got now...

let us know...  and remove check and reinstall those fuses like wmax351 suggested...

j o

[WHITE91K100RS]

Thank you all for the feedback.

Stupid follow-up question; I had a hell of a time trying to get his gas tank off. Is there any trick to it on the 1985 K100? My 1991 K100RS just has 2 C-clips that when removed, the tank lifts up easily.

His 1985 K100 has a plate with 3 screws that mounts to a lip on the bottom of the gas tank. I removed that, but when tried to pull the gas tank, it still seemed attached to something. I barely had enough room to just lift the tank in order to get into the relay box to do some contact cleaning.

[K75RT Keith]

Just the 2 C-clips hold the tank down.  The pins go through rubber grommets and it requires a good bit of force to lift the tank.  Considering that the pins and clips are supposed to hold the tank in place in an accident or spill, they should be pretty snug. 
You can silicone spray the grommets and it help a little.

[WHITE91K100RS]

Alright, we played with the bike quite a bit yesterday and still was not able to solve the problem.

so... what have you done... anything... either way the 1st thing i would do is eleminate a dirty starter by doing this...

put it in 2nd gear... key off... clutch in... roll it backwards... pop the clutch while rolling backwards... do that 5 times...

key on... is the headlight on... if so hit the start button... whats you got now...

let us know...  and remove check and reinstall those fuses like wmax351 suggested...

j o

Rocked it back and forth from second gear into 5th, hit the start button... headlight on, bike fired no problem, blinker problem still persists

Also swapped his speedo with another 1985 speedo, problem persisted (so problem is likely not speedometer). I also cleaned the contacts on his speedo and the pins on the connector... still nothing.

Checked all his fuses, all looked good  (fuse #7 included). Also swapped his flasher relay with mine... didn't solve his problem.

Cleaned up the gear position indicator with contact cleaner at the final drive as well as where it connects near the alternator cover.

I was certain that after swapping speedometers, that would solve the problem... but it didn't.

Any other ideas?

[Scott_]

For testing the speedo pickup sensor......
If you have access to a medium size(say 100watt) soldering iron, you can test the magnetic pickup sensor at the final drive housing.
Plug in your iron, turn it on, and hold it near the sensor(with the ign switch on). You should see the speedo needle move to at least 40mph or better.
If it doesn't move you can trace the wire up under the right side battery cover panel and disconnect it to measure with a volt-meter(a brown wire an a yellow wire).
You should be able to see some sort of an A-C signal(I measured 315mVac) at the connector(the half going back to the sensor). If no signal then you probably have a back pickup, or the sensor ring has come loose/dislodged(though not common, it is possible) inside the final drive.

If you can see an AC voltage signal on the disconnected wire, but you see no needle movement with the connector connected, then you most likely have a power issue to the inst cluster.

Further testing of the inst pod.....
Check for power +12vdc at pin #6 it comes from fuse #1(switched power from ign switch, thru the rh kill switch). Pull the fuse and actually measure it with an ohm meter(continuity tester).
If you have no power at fuse #1 with the ign switch turned on, then you either have dirty/bad kill switch or dirty/bad ign switch or broken wire somewhere in-between.

Here is a link to the lieberry post with the inst pod pin-outs for further testing.
http://www.motobrick.com/index.php?topic=889.msg3477#msg3477

[tg4360]

Gear position switch is at the rear of the gearbox just in front of the swing arm.

Probably almost impossible to get out without dismounting the arm but I'm not sure about that.

The sensor at the FD is just for speed.

[WHITE91K100RS]

Ok, quick update...

After tinkering a bit more, I noticed that his gear position indicator on the instrument cluster is working, tells gear properly as it should. Now the problem is just the turn signals acting like hazard lights when either one is pressed (and the speedometer still not working).

He can live without the speedometer on his bike, but those turn signals are pretty darn important.

Any other ideas?

[tg4360]

Read up on the BMU... might need to be repaired or replaced....

http://bmwmotorcycletech.info/K-hints.htm

Heck.. just for laughs... does the bike have the hazard switch?  If it does... try disconnecting it and see what the signals do.

You don't actually have to have it and can black out the triangle if it's an inspection item in your state.

[WHITE91K100RS]

Read up on the BMU... might need to be repaired or replaced....

http://bmwmotorcycletech.info/K-hints.htm

Heck.. just for laughs... does the bike have the hazard switch?  If it does... try disconnecting it and see what the signals do.

You don't actually have to have it and can black out the triangle if it's an inspection item in your state.

Well, I'll add that to the list of to-do's then... I'll swap his bulb monitoring unit with the one from my bike, see if that changes anything. And yes, I do believe he has a hazard switch on his 85' k100. I'll see what I can do about disconnecting it, just for shits and giggles... see what happens.

Also;

Further testing of the inst pod.....
Check for power +12vdc at pin #6 it comes from fuse #1(switched power from ign switch, thru the rh kill switch). Pull the fuse and actually measure it with an ohm meter(continuity tester).
If you have no power at fuse #1 with the ign switch turned on, then you either have dirty/bad kill switch or dirty/bad ign switch or broken wire somewhere in-between.

I will voltmeter fuse #1 with key turned ON, kill switch OFF.... see if I'm getting any power there. Would you please elaborate a bit more about metering Pin#6? Not sure which pins we are talking about  :dunno2:

[Scott_]

The pins I'm referring to(and the ones in the link) are the female connector that you unplug from the instrument pod when you remove it.

[WHITE91K100RS]

The pins I'm referring to(and the ones in the link) are the female connector that you unplug from the instrument pod when you remove it.

Ok, thanks for clarifying!

I'll pull the speedo again, test pin 6 on the plug that connects to the speedo (and all the rest of them, just because I'm in there...). They should all have 12v+ right? I'll post results next time I get in there.

Just as a crap shoot, I am also going to suggest that he replace ALL of his bulbs. Might cost 10-15 bucks, but it would be good to be sure that some goofy bulb the previous owner bought at a gas station is not the culprit for his problem. Not very likely, but it's worth a shot (feel like we have tried almost everything else)

[Scott_]

You will have to look at the list, but no, not all will have +12 on them. some will be ground's and other will be "outgoing signal" from the cluster for the function listed in the linked documents.

[WHITE91K100RS]

Ok, thanks again for clarifying.

So, the gear indicator on the instrument cluster is working (just not speedo, and turn signals are acting like hazard lights). If the gear indicator is working, wouldn’t it be fair to assume that pin #6 (power) is working?

Regardless… I’ll pull his speedo again and voltmeter pin #6, as well as #17 and #19 (L/R turn signals). I’ll post back results.

[rbm]

There is a PC program, Karamba, available to test the speedo independently of the bike electrics. Try this programs to isolate the speedo problem between either the sender in the final drive or to the speedo itself.  Most likely it is connections to or within the speedo that are causing the problem.

Hazards are enabled whenever pin W on the flasher is grounded.



In the above diagram, Yellow-violet gets grounded and the 4-ways come on.  Maybe there is a wiring error in the relay box or within the harness that is causing yellow-violet to ground when the indicators are pressed.  Pins TL and TR are the connections to the indicator buttons on the handlebar switch assemblies.  Pin TA is the cancel switch.  Grounding any of these will engage their functions (i.e.  TL blinks left; TR blinks right; TA cancels blinking).

As suggested earlier, disconnect the 3-pin plug to the hazard switch.  If the problem persists, either the flasher is possibly defective or there is something continuing to ground pin W.  Trace wiring to see if that is the case.

[1991K100RS]

Bit of an update in the 1985 K100 RT blinker issue been trying to resolve.......

- I noticed that when brakes are engaged, the brake light goes on as well as the L/R rear turn signals also behave like brake lights.

- Took the speedo off, voltmetered pin #6 (power) -confirmed 12v. Volt metered pins #16/19 (L/R signals), both had power when signals engaged.

- When instrument cluster (with faulty speedometer) is removed from bike, turn signal issue still persists. Confirms blinker issue is not a result of the instrument cluster

- Removed the Impact Plate from his bike in effort to unplug flasher switch. When I had access to the back of the impact plate and back of hazard switch, I could not find any practical way to unplug or remove flasher switch. Seemed like the 3 pins connected to flasher are soldered on and switch itself is wrapped in the plastic material the impact plate is made of.

So... after noting that the turn signal engaged activates hazard lights, and the brakes engaged activate the turn signals as if they were brakes I am confident the issue is a wiring mix up.

Thoughts?

[johnny]

greetings 1991k100rs...

backaway from the redd mushrooms...

j o

[Inge K.]

I would guess you have a bad ground connection in the tail.
You find a multi connector behind the tail light,the brown wire is ground.

Check that the connector is clean and free for corrosion.....and/or try With a piece of wire/test pin/alligator clip....or similar to make a temporary ground connection, and see if it makes any difference.

[rbm]

- Removed the Impact Plate from his bike in effort to unplug flasher switch. When I had access to the back of the impact plate and back of hazard switch, I could not find any practical way to unplug or remove flasher switch. Seemed like the 3 pins connected to flasher are soldered on and switch itself is wrapped in the plastic material the impact plate is made of.

The hazzard switch lead first has to be disconnected from the harness under the tank.  Then push the switch out of the dash pad from the rear.  It is a friction fit within the hole,  two clasps at each end applying pressure to hold the switch in the dash pad.

[orforester]

I say starter brushes are dirty or you need new ones, go with the easy, first.

[johnny]

im with the orrforresterr...

the 1st thing i would do when expieriencing electrial whackness is this...

http://www.motobrick.com/index.php?topic=5678.0


j o

[Scott_]

I would guess you have a bad ground connection in the tail.
You find a multi connector behind the tail light,the brown wire is ground.

Check that the connector is clean and free for corrosion.....and/or try With a piece of wire/test pin/alligator clip....or similar to make a temporary ground connection, and see if it makes any difference.

I'm thinking along the same lines with Inge on this one. Check your grounds in the tail cowl.

[1991K100RS]

im with the orrforresterr...

the 1st thing i would do when expieriencing electrial whackness is this...

http://www.motobrick.com/index.php?topic=5678.0

j o

Thanks for the responses fellas. I already tried the ole' rocking it back-and-forth from 2nd into 5th with power off trick to see if I could confirm the problem was dirty starter commutator, turning power on and seeing what happens... didn't change any of the symptoms.

-Still haven't replaced the light bulbs, so we're going to do that soon just for shits...

-Also, I didn't think about multi-connector for the turn signals. I'll find it in the cowling and clean up those pins.

-I also have a spare starter lying around in the garage, so I'll swap the starters, see if that resolves it.

I'll report back with findings soon :)

[jacksdad1963]

I'm with the guys who say its a bad ground/earth thats causing all the problems  :2thumbup:

Its like following a car, when the driver turns on a indicator then brakes, all the lamps go crazy, dimming/lighting up or not!
Its a bad earth every time, so I'd try running new earth cables from the battery earthing strap to the relevant contacts on the bulb holders....reckon that will fix it!