turn signal problems

[tmctguer]

a few months ago, i did some work on my passenger side blinker light assembly to allow for me to remove it during track days so i would get more air flow to the fender mounted oil cooler. upon reassembly of my work (basically, just extended the wires via electrical connectors so i could have some slack in the wires), the signals worked fine.

a few months later, after actually removing the front signal assembly at a track event, and reassembling the unit, the front passenger no longer would blink when using my turn signals. the rear light blinks just fine. initially, i suspected a fault in my wiring. i checked that and it was all OK. i cleaned all the connections just to make sure i was getting a good ground. that did not help anything.

just to make sure it wasn't a bulb, i swapped out bulbs from the right assembly. the bulbs weren't the problem, as the known good bulbs did not work in the passenger side light assembly, and the suspected bad bulbs worked fine in the driver's side light.

to further test, i noticed that when i turn on my headlights, the light assembly works just fine and both bulbs iluminate. so, when iluminated as part of the overall front light circuit, all is well.

i bought a replacement turn signal relay from a local shop that wasn't a porsche unit, but a BMW unit that had the same bosch part number. when i installed it, the entire blinker system went wacky so i discounted the BMW unit as a non-matching part.

i read somewhere that most electrical problems are from bad grounds, so i double checked the grounding of the light assembly. it was intact, as far i could tell from the exposed wires that are part of the assembly.

so next, i'm going to buy a REAL porsche blinker relay from PP, and we'll see if that fixes the problem. in the meantime, does anyone have any ideas what i could do to further troubleshoot the problem?

[Emission]

I just got my blinker back to working condition. The parking lights worked, but the front left blinker did not.

Check these things:

Does the light illuminate for Parking Lights?
Does the light illuminate as a Blinker?
Does the light illuminate as a Hazard Light?

If the light works for a hazard light, but not for a blinker, it is your turn signal switch. If it works for neither, than it could be the bulb, or the wiring. If the bulb is fine (check it off the car), then test the light assembly. Most likely it is corrosion or your ground.

Mine had tons of corrosion which needed to be scraped off. I cleaned it all up (especially the GROUND on the back of the light assembly), then put it all back together with DIELECTRIC GREASE. It works now.

P.S. - I have a slightly used (< 2 years old) turn signal assembly (OEM Porsche) that works fine. I accidently replaced it troubleshooting something else. If you need it, I will sell it to you for cheap!!! E-mail me.

[tmctguer]

after months of looking for this one -- BINGO................i solved my problem !!

as i mentioned in my original post, i had disassembled the front signal assembly at a track event to get more air into my oil cooler assembly. i suspected this could be the source of my problem.

after disassembling the working turn signal, i could see that there was nothing missing in the non-functioning unit. i took a volt meter and saw that the working unit was getting voltage when the switch fed it. i took apart the non-working unit and checked the same voltage. i had a reading........that didn't make sense since the lights would not illuminate via the turn signal switch.

i then turned on the flashers. only the working assembly lit up. i started fiddling with the light bulbs on the non-working unit (even though i knew they worked). i removed a bulb and attempted to reinstall it. i had it backwards, but when i pressed it into the hole, the thing flashed. i installed the bulb correctly in the hole, and it didn't flash. i removed it, pushed it in the hole backwards again to make contact with the copper connections, and it flashed.

ahah !!! it dawned on me that when i had reassembled the light fixture, i had switched the two electrical wires connected to the copper connections. the bulb receptacle was in reverse polarity !

i removed the connections, reversed them, reinstalled my bulbs and VOILA..........the turn signal assembly worked again.

i've been chasing this problem (infrequently) for the past 8 months. it feels great to have finally pulled the needle from the haystack.