Headlights

[Ruxin]

Need some help with nonworking headlights in my 1988 911. I replaced the switch last year (purchased from this site) and all was well. Now, the first pull turns on the running lights like it should and the dash lights work with normal rheostat. On the second click neither of the head lights come on. Unlikely that both bulbs are burnt out at the same time. At $550.00, I'm hoping that its not another bad headlamp switch. If so, why would it crump so soon? Any help/ideas are appreciated.
John

[lsf911]

I would start by pulling out a headlight and measuring the voltage at the terminals. Should be 12V when you pull to second click on the headlamp switch. If the voltage is not there then you know it's not the headlamps (which I agree is not likely that both went at the same time).

Do you have the headlamp voltage relay installed? If so, could be the relay or fuse in that harness?

[Ruxin]

Thanks Lou. I will do that first thing in the morning.
John

[Quickstep192]

I’d use a volt meter and see if there is 12v to the output terminals on the switch. If there is, check for 12v at the bulbs. If there’s 12v at the switch, but not the lights, start looking in-between.

I’m not 100% sure, but there might be a relay in there. .

[86 911 Targa]

Three possibilities:

The headlight relay.

The switch connections.

or:

fuses #4&3 on fuse block #3.
(Although not probable)

Do you have the headlight relay upgrades?

pm me as needed.

Best,

Gerry

[86 911 Targa]

G.

[Tea Tray]

It might be easier to check the headlight fuses for power.

[timmy2]

Originally Posted by Tea Tray

It might be easier to check the headlight fuses for power.

Definitely the first and simplest place to check.
Switch on, should see 12 vdc from the top headlight fuses to battery negative, and the same from the bottom of the headlight fuses.

And yes, both lamps can burn out at the same time. Happened to me with some ”new and improved” higher output H4 lamps. Originals went back in, have lasted many years since.

[Ruxin]

So I check the fuses with the voltmeter and I get zero reading at fuses 14, 15, 16 and 17 on both top and bottom of the fuse (neg to neg on battery terminal). I checked the headlight switch at 58R and 58L and get 11.5V. Get 12V from battery. No voltage at the headlight harness. Sorry guys, I'm definitely a newbie here. Thoughts?

[timmy2]

Ignition on? Headlight switch fully pulled out?
58 R&L just tell you the running lights work.
Headlight yellow and white wires run through the turn signal switch. Nothing to the headlight switch.
Make sure the 6 pin connector coming from it to under the dash is fully seated.

[Ruxin]

Thanks for all the help. I was literally standing there scratching my head after checking everything over again. The headlights went on. What? I reinstalled the lights in the car and NOPE. Out again. I looked at the fuses once again and everything seemed sorted and they came back on again. I have to assume there is a loose wire somewhere that I can't find. Lights are on now but not sure for how long. I don't smell anything burning.....

[darrin]

You might first want to check to make sure there isn't any discoloration/oxidation on the headlights' fuses/holders --

[timmy2]

Pull the headlight fuses, clean the metal where they touch and slightly tighten the screws if loose.

[timmy2]

Do you have auxiliary headlight relays installed?
It was asked earlier.