r-mm

For a while I had temperamental reverse lights. A month back I re soldered the wires on the switch itself, after verifying with DVM that the switch works and has no resistance. Also verified lights worked when I bridged the two pins to each other outside the switch. Lights seemed to work for a bit then stopped entirely.

Today I verified that the relay (#1) is working (audibly in Central Electrics and on the bench with a power supply and DVM), swapped it with another for good measure: all good. Aside: if the reverse light relay #1 were bad, the fog lights would also not function. For reasons I can’t figure out Porsche gave the fog lights TWO relays (#1 feeds #31) and the headlights none…

Then I removed the lights and 3 pin connector, verified I had 12v at the chassis side. Plugged the connector back in, verified I had 12v at the two spring metal contacts inside the sockets. Then I tested the light bulbs with a 12v power supply. ALL. GOOD.

The god damn bulbs will not illuminate. I thought perhaps the spring contacts were deformed so I pried them out some and checked again, no light. Then I pried more and broke one : (
Only thing I can think of is the bulb itself is incorrect? It is a two pin bayonet that seems to fit perfectly. Tried jiggling it etc. Forgot to take a pic of the bulb.

I remain, frustrated. Anyone dealt with something similar?

Spyerx

Reverse bulb is a 7506 / 1156 type single filament

r-mm

yep thats what I got, a proper made in germany osram 7506...

wallra

did you check the ground in the light socket

r-mm

Because I saw 12v with my DVM probing the socket I think the answer is yes, that effectively checks that the socket is seeing a good ground. I've previously cleaned GP XIV where that ground ends up (engine right, rear) but will re-check it today.

r-mm

Anyone have the part number for that lampholder? I checked the electrical chapter and came up blank.

Jeff Burger

depends on where you had your meter grounded.. - going over what you have done sounds like you are capable so if this is obvious sorry just trying to help - I fixed my back up lights on my 92 last spring.
1. use your ohm meter to see if the brown wire on the chassis side of the 3 pin connector is shorted to ground. by hooking one side of the meter to a metal chassis ground. -- wiggle wires make sure it isn't intermittent
2 next use your volt meter to see if you have 12v from the trans switch wire in the connector to the ground wire in the connector. (while key is on and in reverse) careful not to short together
3. if not fixed the connector may not be making the connections - wiggle plug and unplug a few times.
4. If that doesn't work now check both ground and power at the bulb socket - careful not to short the two.

Golf is done for the next 3 months so I have time and I'm not too far over the state line if you want to bring the car over. I'm sure together we can get it.