David Carter

I'm also having an issue with my 1985 928S fog lights as well. I'll try to give a concise rundown of what I've found so far. To start there is no power at fuse 30. Fuse is good and I've swapped multiple ones to be sure. I then moved to the fog light relay XIII. After swapping relays with other working relays and still no success, with a test light I found that I only have power at terminal 86 with the ignition on, headlight on low beam and fog light switch on. There is no power on terminal 30. When I turn the high beams on I have power at terminals 85, 86 and 86b. I can also feel the relay click when I toggle the fog light switch off and on. I have also checked the relay at IV and swapped it with other working relays. I have also jump the terminals 30 and 87 at relay IV with no success. My thought is my problem lies in not having power to terminal 30 at relay XIII. Am I missing something, is there anything else I should check? Any input would be greatly appreciated.

Thanks
David

linderpat

Thread revival - did this problem get resolved? I have a similar issue. I put in a good known relay, no joy. Bought a new fog light relay just in case, still no jpy. Fuse is good (15 amp, position 30). I swapped the switch with a spare fog light switch, no joy. The fog light switch does light up, indicating that it is getting power. Fog lights did work, but I had other headlight issues which were resolved wen I played with the combination switch. I also put in a new combination headlight relay, for whatever that's worth. What's next?

Mrmerlin

I know you prolly checked them BUT but please test the bulbs.
3 cars already with both bulbs blown

linderpat

Thanks Stan. Will check them. Seems crazy that both bulbs would have burned out at the exact same time though, but I agree, they should be tested.

Mrmerlin

both bulbs failing could be from hitting a good pothole at speed this could fracture the elements

linderpat

That did not happen. They stopped working after I pulled the combo switch and replaced it with another known good one, then tested my lights which were causing problems. I put the original combo switch back in. I don't know how/if the fog lights tie into the combo switch.

Here's the tortured history: When I got the car, the following occurred:

• put on parking lights only, not fog lights, then flick hi-beam lever to "on" - causes headlight buckets to cycle continuously up and down, until hi-beam turned off
• The above did not happen if the fog light switch was activated - i.e., fog lights on (the fog lights were working fine too, neither burned out).
• replaced big headlight relay with spare - no difference, headlights still cycle up and down when park lights on, fog lights off
• replaced combo switch with spare - no difference, headlights still cycle when park lights on, fog lights off
• re-installed original combo switch
• fog lights no longer work, but headlights no longer cycle up and down when the hi beam lever is activated
• replaced fog light relay with spare - no difference
• replaced fog light switch in pod with spare - no difference
• got new relays from Roger - fog light and headlight - replaced and no difference - fog lights do not work

Mrmerlin

With more info please disconnect the battery remove all the pod switches look up the part numbers and then confirm the switch identity
Note each switch has a part #
Note the wire layout of the connectors are in the correct places
you wouldn’t be the first to put a similar switch into the wrong connector
Also make sure you have the correct relays in the correct positions on your CE panel a wrong relay can cause fog lamp failure

Wolfman928

wow, this is really odd, I was about to ask you what did you do or change before they stopped working, this is really odd ? I have replaced fuses and relays for all my lights and they still work, I only removed my fog light switch to clean the electrical contacts...

freddyuk

I have exact same issue, UK car 1985 s2. It’s about to go in for the Mot and likely fail on this 🙁

Meatful

freddyuk

Will check relay 4 on my '85, thanks for posting this mate

Wolfman928

ok cool ! glad you picked that up...

linderpat

That relay 4 is a great find. I will try to swap it next (Car in storage for the time being)

Darklands

OK, looks like I‘m also a victim of Relais 4.

Darklands

Thank you for this great ressource of knowledge!