Well here it is:

I recently replaced my multi-function switch with a "guaranteed fully-functional" used switch from 928 Intl. as the old one wasn't functioning properly. Everything works properly now except when the headlights are on applying the left turn indicator causes the headlights to flash (low to high beam) in time with the turn signal! Works fine with the right turn signal and fine both directions with headlights off or even with parking lights on. One other strange thing is when the headlights are on and I switch the emergency flashers on the headlights will flash also. Not sure if that is the way it is supposed to be or not but i can't imagine having the flashers and the headlights on at the same time anyways.


Any ideas on the left turn signal-flashing headlight dilemma? I'm stumped. Ground problem somewhere?

TIA

 

Shake a chicken bone over the CE panel and spin around 3 times.

First step in all 928 electrical troubleshooting

But no, the headlights are not supposed to flash with the hazard lights.

Pull relay V, that should be the blinker relay. See if the headlights still have any problems when you move the blinker lever with the relay out.

I'd start there.

Then I'd take the fuses out one at a time for the blinkers, there are 2 per side (front and back) and try to isolate where the cross connection is. Sounds to me like the hot side of the headlights is crossed up with the blinkers somehow.

Does the behavior change when the headlights are on hi beam vs low beam? There are 4 fuses for that too, I'd pull and replace, checking function. 2 for low beam (L/R) and 2 for high beam. Pull the high beam fuses and see if the problem stops with just that. If the high beams still flash with their fuses pulled that would show something as well.

LOTS of fuses and relays in the system there to go wrong in addition to grounding. Methodical pulling of fuses seems to help me isolate these voodoo things.

 

Check all the grounds especially in the left turn signal circuit. does the high beam indicator in the dash actually ligh up or are you saying they flash low to high based on headlight beam intensity? also does the beam get brighter or dimmer when the signal is iluminated or during the off cycle? is it both headlights or just the one on the left side that changes brightness?

 

Thanks for the reply.

The high beam indicator on the dash flashes off and on with the left turn indicator. The beam doesn't seem to get brighter or dimmer, they just flash nicely. Both headlights flash at the same time.

Do you know where the ground for the left turn signal circuit is?

 

Check the grounding in the pod - how much did you remove to do the install - the whole pod? or just the steering wheel?

This certainly sounds like a grounding problem - that is almost always the case when 2 unrelated circuits start interacting with each other as here.

Alan

 

Thanks for the reply jayc67.

I'll try removing the flasher relay and then try the turn signal. What do you mean by problems with the relay out?

Doesn't seem to matter if the headlights are on low or high beam, same result.

I'll check the fuses too, but don't think any are blown. If the high beams still work after i full the fuses then I'll be really worried...

Off to the garage....

 

Thanks a lot for the reply Alan.

I only moved the pod up a little to pull the old switch out and install the new. Where are the grounding points in the pod?

 

What I mean is that with the blinker relay out, moving the blinker lever up or down shouldn't do anything. If problems happen with the relay out, there may be some wiring crossup in the switch, before even getting to the panel. Wouldn't expect it, but it's pretty easy to eliminate lots of stuff, and weirder things have happened.

Eliminate the easy stuff first, even the things that sound totally bizarre

Not that they will be blown, but if you pull fuse to light X and that light still fires up then you know there is crossed wiring somewhere. That's the point of pulling the fuses one at a time, to make sure something isn't wired to the wrong circuit. May not have anything to do with it but again, easy process of elimination.

 

Well I took the relay out and while using the indicator switch i could find no connection to the headlights. I don't think the problem is in the switch. I did notice that the flasher relay makes a different noise (more of a thunk) when the left indicator is on versus the right which makes a quieter noise. I wonder if the flasher relay is bad. Of course it is a unique relay to the car, can't sub another to check it. It is marked as a audi/vw part so perhaps I can get one fairly close by at the audi/vw dealer here in Ballard. I'm going to try that next for lack of good ideas. One strange behavior is when i pull the turn signal lever back to the "flash to pass" position the headlights flash fine but the left front and rear turn indicators flash also. I know this isn't right and perhaps this is the root of my problem. ????