Headlight diagnostics

[massive]

Got a problem where my headlights go up but won't come down.

I troubleshooted some previous headlight problems a few years ago that I documented in my blog so I am quite familiar with how the system works.

Unlike last time I believe the switch may be the problem this time around because I'm only getting 6-7v on the red/green wire at the molex connector when the switch is in the off position (should be 12v according to clarks garage tutorial)

I've taken the switch apart and cleaned out the inside, there does seem to be some wear on the contacts, I've reassembled it and still the headlights go up but not down

Is there a way to further test the switch or a way to simulate the operation of the switch by sticking a wire or two into the switch connector?

Regards

[massive]

Here's some pictures of the back and inside of the switch, seems to be some wear on the bottom set of contacts, not sure if there was meant to be a raised nipple (on the bottom contact plate) like all the others seem to have?






Here's a diagram of the continuity findings from my switch, I'm now not so sure the switch is the problem as all the continuity contacts seem to function correctly.




Now that I know the switch positions maybe I'll try some jumper wires on the switch connector block to simulate the switch and see if that works

[mattdavis11]

Just curious, do your tail lights and side markers work? I have the same problem with the head lights, and have concluded that I no longer have a constant 12v from the battery to the switch. Ignition and main lead for the head lights both have 12v.

If I disconnect the battery for awhile, the head lights go down as soon as I reconnect it.

[massive]

Yep all lights are working as normal, will do some more testing over the weekend and solve this hopefully

[massive]

Okay, solved this problem and put together a new write up that may help some others in the future.

http://944foot2thefloor.blogspot.co.uk/2015/10/how-to-troubleshoot-porsche-944.html?m=1

[djnolan]

Nice write-up. Question, does this procedure apply to a late car, in this case my 87S? The headlights didn't retract when I pulled in to the drive tonight.

[massive]

Is yours a square dash or oval dash model?

[djnolan]

Originally Posted by massive

Is yours a square dash or oval dash model?

87 944S - oval dash

[massive]

The mechanism and motor electronics will be the same, but the electronics going to the fuse board and the switch will be slightly different. The oval dash version has a fuse on each wire (4 fuses in total I think) I would check those first.

[djnolan]

They went down by themselves overnight. Maybe something is sticking. I will play around with it this weekend.

[massive]

Originally Posted by djnolan

They went down by themselves overnight. Maybe something is sticking. I will play around with it this weekend.

Sounds like that could be your issue then

[pvnano944]

Dear Massive,
Would you happen to have the pin out by wire color on the headlight switch, for example, 56=blue, x=black,58r=red...thank you