Lovemyevo2

Hi all, a new problem rather than one that came free with the car :-)
Having worked fine since I bought the car the headlights stopped working recently. They popped up but no light. The square bumper lights below seemed to work fine. Following research on the forum I thought it must be a relay problem. Also I'd had a couple of weeks of nasty electrical / shorting buzzing noises from the fuse / relay board when driving about although I hadn't worked out exactly where it was coming from and it didn't seem to have a pattern. But when the lights died this problem stopped. So I broke open the relay and couldn't see anything obvious and concluded I needed to buy a new relay, which I bought from Porsche UK.
Now with the new relay I seem to have my low beam working but no high beam. There is voltage to the yellow wire on low beam but no voltage to the white wire when I push the dash lever forward. No blue light on dash either.
All fuses seem to be okay.
Any further suggestions that might help me out?
I forgot to say that the outer square bumper lights come on fine when the lever is pushed forwards. The problem seems to just be with the pop up lights.
Thanks Tim

Mrmerlin

what happens with the headlights on and low beam selected,
and then you pull the turn signal switch lever backwards do the hi beams flash?
if so then you may need a new switch

Lovemyevo2

Nope, same deal when the lever is pushed or pulled. Pop up lights go off and the high beam bumper lights fire up.

Mrmerlin

check the hi beam bulbs as they could both have failed,
there is another thread that has the same outcome,
both hi beam lamps were failed

Lovemyevo2

Worth checking. I presume I can test the bulbs by taking a wire off the battery?

Mrmerlin

you can check the bulbs by looking for continuity and or applying 12v to the bulbs.
one pin is ground the other two are for lo and hi beam filaments

Lovemyevo2

Hi all
I've done further checks on this. continuity of bulbs is fine. There is no power to the white wires within the bulb harness - then working back there is no power to the two high beam fuses when the lever is pushed forward or flashed (there is power to the two low beam fuses next door when the lever is in the back position) Any ideas on where to check next. I'm presuming the lever switch is okay, I'm also presuming the relay is good as it's brand new. So what else is there to fail? Thanks, Tim

Mrmerlin

What was the last thing you fixed?

Lovemyevo2

Hi MrMerlin. I replaced the passenger window switch. I removed extraneous wires that have been spliced into the fuse / relay board that were for an old car phone set and an after market alarm. I also removed the glove box to remove the wiring that went through the firewall behind the glovebox that weren't attached to anything in the engine bay). Also for an alarm apparently.
Removed additional wiring that went to the rear of the car, which someone said might have been used for a tow bar historically.
Cleaned up all the interior light connections and door switches to get them working correctly.
As I'm writing this it does make me think that there's been a lot of messing around, adding additional wiring by POs. each time wiring has been added the standard wires have been cut and connectors added. I wonder if I shouldn't work through all these and re solder the connections with proper connectors?
Does any of this trigger any ideas??
Tim

Mrmerlin

well I would of course remove any non factory wires and fix the cut wires properly,
once this is done you may find that all of the lights and other things operate as they should ,
its quite common for the alarm installers to cut into light harnesses to add the blinking light feature that tells when the alarm is armed

Lovemyevo2

Mmmm. Removal of the board and a night of soldering looms...

Rich9928p

Helped a friend fix his headlamps. Each headlamp (L & R, high & low) is individually fused. Check voltage from the fuse (top and bottom) and then where it exits the Central Electric (factory workshop manual shows which plug/position).

My friend's problem was wires were broken under the headlamp (access from fenderwell). Repair the break and the headlamp worked.

A volt meter and schematic diagram is your friend.

Lovemyevo2

There is no voltage either side of the high beam fuses. The problem must therefore either be within the CE or the switch rather than up front. I will get a workshop manual and start sorting the CE.

Lovemyevo2

Okay, I'm coming back at this problem as I finished removing all the poor quality connectors around the CE board and soldered up the wires correctly. But still the high beam doesn't work when the lever is pushed to the forward position or pulled to flash. To recap the bumper high beams come on fine but the pop up lights switch off. There is no dash high beam indicator light.
I refitted the old relay, which i replaced and with this in the lights pop up but there is neither high nor low beam from the pop up lights. (When I bought the car both worked). The part number written on this is 92861810700. The new relay I got from Porsche UK has a different part number, 92861810705 as I was told the part number had been changed. Both relays are the 'double' type but the old one has a silver metal case and the new one a black plastic case. Could this new relay either be wrong or faulty? Is there a procedure of testing the relay harness to check everything is operating correctly 'behind' the relay.
I'm still buzzing after solving the stop lamp warning problem so this would make me very happy to solve. Thanks Tim

The Forgotten On

I had the same issue with my 1981 U.S which I put 8 inch H4's on, I even replaced the large relay with the plastic new one and it didn't work just like yours did. The plate that goes on the back of the H4 assembly that goes in between the H4 bulb and the harness itself can develop corrosion internally while it looks okay on the outside. Check this by taking the plate off of the back of your lights and plugging the bulbs directly into your harness. If they work then find some plates to replace your corroded ones. BTW the metal relay worked after I tried this while the plastic one never did to begin with. Good luck.