Fog Light Help

[dagersh]

Hi Guys,

The Fogs on my '89 Targa are not functioning.

The relay works, I switched it out to the horn position to check its function, and it worked fine, plus you can hear it actuate when sliding it into its holder.

The fog light switch on the dash has power and lights up in the on position

The bulbs are working as well.

So in my searches on the BBS, I see there is a relay, which I can only assume is either disconnected or fried.

I recently replaced both the Headlight switch and turn signal assemblies on the steering wheel as they were both burnt out and beyond the simple repair. To finish up the repair to the switches, I installed our host's headlight relay kit, and now the lights all work as they should - except the fogs - which were working before the switch replacements.

So my question... where is the relay? How can I test it?

Thanks for looking! This site was a huge help in my lighting woes!

[86 911 Targa]

Originally Posted by dagersh

Hi Guys,

The Fogs on my '89 Targa are not functioning.

The relay works, I switched it out to the horn position to check its function, and it worked fine, plus you can hear it actuate when sliding it into its holder.

The fog light switch on the dash has power and lights up in the on position

The bulbs are working as well.

So in my searches on the BBS, I see there is a relay, which I can only assume is either disconnected or fried.

I recently replaced both the Headlight switch and turn signal assemblies on the steering wheel as they were both burnt out and beyond the simple repair. To finish up the repair to the switches, I installed our host's headlight relay kit, and now the lights all work as they should - except the fogs - which were working before the switch replacements.

So my question... where is the relay? How can I test it?

Thanks for looking! This site was a huge help in my lighting woes!

Here you go:



Also, the factory wiring uses the fogs only when the headlights are on.

So there may be an issue with your repairs.

Here's the head light switch wiring from our '86:



I rewired the fogs to operate independent from the light switch:





Here are the relay kit connections as per our '86:



Good luck,

Gerry

[dagersh]

Gerry,

That's great. I am sure on my Headlight switch repairs.

Am I moving (x-tending) the Gray wire to #11 for a constant power? Sorry, I am not at the car so I cannot check what #11 controls.

Is there anything else I would need to move?

Thanks!

Michael G

[dagersh]

Wait - I think I get it!!!!

#11 is #8 in the second fuse box, correct? Red 16A fuse?

If that fuse is blown, my Fogs would not work.... maybe that's my problem?

Thanks,

Michael G

EDIT:

That's not it. I will try extending the gray wire from 20 out to #11. May be its my headlight switch repair afterall, but i swear everything is in the right place, and the switch is brand new. The headlights and indicator/parking lights all work as they should.

I will also check the gray/white wire on the switch, maybe it came off....

[DRACO A5OG]

Check the grounds, the Bosch H3 bulb actually uses the metal housing of the fog lamp as ground source, you can see it when you remove the lens, a metal tab at the bottom of the assembly, it has to be clean and corrosion free. Take a DVM to it and you will see it reads 12+ volt.

[86 911 Targa]

Originally Posted by dagersh

Gerry,

That's great. I am sure on my Headlight switch repairs.

Am I moving (x-tending) the Gray wire to #11 for a constant power? Sorry, I am not at the car so I cannot check what #11 controls.

Is there anything else I would need to move?

Thanks!

Michael G

That's it.

There is always power to fuse #11 when the ignition is "on".

Gerry

[86 911 Targa]

Originally Posted by dagersh

Wait - I think I get it!!!!

#11 is #8 in the second fuse box, correct? 16A fuse?

If that fuse is blown, my Fogs would not work.... maybe that's my problem?

Thanks,

Michael G

That's correct, but why is the fuse blown???????

[Bob Kontak]

Originally Posted by DRACO A5OG

Check the grounds, the Bosch H3 bulb actually uses the metal housing of the fog lamp as ground source, you can see it when you remove the lens, a metal tab at the bottom of the assembly, it has to be clean and corrosion free. Take a DVM to it and you will see it reads 12+ volt.

+1 - pulled my hair out over this one years ago.

[Carbster]

First rule of old car and bike wiring repair. Check the ground/earth, then check the ground again. I also check connectors and connections. Ive seen wire corrode inside the rubber housing but at the solder or crimp joints this area is very prone to loss of connectivity and breakage. A test light and voltmeter with continuity tester and invaluable. A test light and a long jumper lead can be used for most everythingnand are dirt cheap.

Having old bikes and cars a test light, tape and butt connector has saved my ass more times then I can remember and gotten me home.

[dagersh]

Draco - Do you mean the metal tab on the pot metal that holds the lens/reflector assembly in?
I did not see any other place other than the ground wire attaching to the back of the relector which grounds the bulb itself....

Gerry - The fuse was not blown, it just looked it. I used my MM to confirm its continuity. I will try to pull my headlight switch again to see if maybe the Gray/White wire has come loose.

Carbster - as someone also with many old bikes and cars, I could never live without my MM and Test light!

Michael G

[86 911 Targa]

Originally Posted by dagersh

Draco - Do you mean the metal tab on the pot metal that holds the lens/reflector assembly in?
I did not see any other place other than the ground wire attaching to the back of the relector which grounds the bulb itself....

Gerry - The fuse was not blown, it just looked it. I used my MM to confirm its continuity. I will try to pull my headlight switch again to see if maybe the Gray/White wire has come loose.

Carbster - as someone also with many old bikes and cars, I could never live without my MM and Test light!

Michael G

Prior to any intrusive analysis, turn on headlights, then fog lights, and check for 12V:



Then pm me.

Gerry

[dagersh]

Ahhhhh - been a while.

I figured it out. Wiring was just fine. The problem was the 25A fuse. I had checked the continuity multiple times, however, at higher Amps, the fuse was failing. On a lark, I replaced the fuse with a new one, and Voila! fog lights are working just fine.

Lesson Learned!

Gersh