AndrewM

Car is a 86 930 with H4's.
One day the low beams just went dim, but the high beams were fine as well as the flash function.
Turn Signal stalk is new, even temporarily swapped in a good used one...no change. Fuses are all new. Checked and cleaned the ground by the battery. Opened up the H4 buckets and all wires are proper and even swapped out the bulbs.....no joy.
Voltmeter time.....I have 6v going to the low beams and 12v to the high beams at the headlights themselves. HOW is this happenening? I have 12v at the low beam and high beam fuse blocks when that particular beam is selected.
Any ideas? Can the headlight switch do this? It dims the dash lights well and all the connections are good.
I'm loosing my mind!!!!!
Thanks,
Andrew
86 930
Autronic EFI

Steve Weiner-Rennsport Systems

Check:

Battery connections & cables and grounds VERY thoroughly.

Check alternator output for 13.8-14.2 @ 2K RPM at the battery terminals.

Make sure the fuses and contacts are not oxidized. Fuses can LOOK fine, but be defective. Make sure the crews holding the wires to each terminal are tight.

Check the connector on the high beam switch, assuming that its already in perfect condition. Cheap ones don't last long, nowadays.

Check the headlight switch for voltage drop & resistance. You didn't say how many miles are on your car, but these don't last forever.

I'd guess the high-beam switch is bad, but there is more work to do before condemning it.



I'd strongly recommend installing a set of relays once you find the trouble,....

AndrewM

Battery grounds and connections.....clean
Fuses new and checked, all wires into blocks tight
13.8V at 2000 rpm's
By High beam switch do you mean the Turn signal switch? If so, high beam is great and also replaced this switch to double check...same result.

By "checking the headlight switch for voltage drop and resistance" this is of course the on and off switch with the dimmer, correct?
I checked pins 75 and 56 and both had 12 V...how and where do I check for resistance and voltage drop?
Thanks Steve.

AndrewM

Problem fixed:
Well....turns out I had the H4 leads misplaced....The Ground Wire was in position 3 instead of position 1......
All in all it only cost me a day in the garage and a used Turnsignal Switch
I bought here on Pelican classified.
Here's the thread that I had looked at before to see if I had the bulb wiring right, but maybe I was to tired or dumb since I still managed to reverse them! I caught it just now.

http://forums.pelicanparts.com:80/sh...dim+headlights

All is well.
Thanks to L.J, and all that helped!!
Drew
86 930

theiceman

beat me to it , sounds like you had them hooked up in series ..

theiceman

Still.. very good advice to run them through a relay ... headlight switches aren't cheap..

Grant Hall