Light problem

by **JackT** » 07 Apr 2007 0:07

A little help with this one, please...... when I turn on the headlights, my dash lights,side marker lights, taillights and front running lights do not come on. The front and rear turn signals work as do the brake lights. All the fuses are good, so where do I look to solve this problem?

by **dave-r** » 07 Apr 2007 11:00

I had this problem myself. It was the side/headlight switch. I could switch the side/dash lights on but when I the switched to headlights the dash and sides switched off.
I managed to find a new one on ebay. I had to swap the toggle over but apart from that it was straight forward.

It was much better but I also had another problem.

Sometimes on some parts of the dimmer the dash lights still went out.
So I shorted out the dimmer. The dash lights are full brightness when switched on now but, as they are not all that bright, that is fine by me.

by **Eddie** » 07 Apr 2007 14:06

JackT wrote:A little help with this one, please...... when I turn on the headlights, my dash lights,side marker lights, taillights and front running lights do not come on. The front and rear turn signals work as do the brake lights. All the fuses are good, so where do I look to solve this problem?

Jack, my instrument lights wouldn't come on and the front turn signals wouldn't work. It was a short to ground in the front headlight bucket, I thought we were going to have to take the dash apart, which was not necessary. Before you break out the DVM,(digi volt ohm meter), try unplugging the headlight wiring or wiggling the wiring to see if you can make the lights flicker, if they do you have a short to ground somewhere. A test light should show 12 volts to those accessories that arent working. Resistance would be infinite if it's an open wire. Also, make sure all your bulbs are in working order, just because it doesnt luminate doesnt mean the filament is open, it could be corrosion causing a short. I would try all the "basics" before dissassembly. Let us know!

by **JackT** » 07 Apr 2007 15:30

Since the front and rear turn signals, brake lights and emergency flashers all work properly, I am assuming the grounds are all good. With that taken into consideration and the good fuses, I think this is a power source problem. Looking for common points in the three areas of forward light harness, rear light harness and dash lights, the headlight switch leaps to the head of the line the way I see it. I'll let you know what happens...... now where did I put that spare switch?????? Thanks Eddie and Dave!

by **Eddie** » 07 Apr 2007 16:04

Yes, Jack, the main feed connector, and downstream wiring, measuring resistance to those areas in question. Good luck, let us know as we can all learn from it. I think,as you "measure", resistance infinite=open short such as wire that is broken but not touching a conductor. Resistance very high such as 100k ohms= short to ground as I recall. Such as a broken wire touching the frame or housing.

by **JackT** » 07 Apr 2007 23:43

It was the pink wire from the fuse box to the headlight switch...... no power was getting to that side of the switch. I checked the rear light harness by unplugging it and jumping power to the black wire in it from the battery terminal on the fuse box..... the lights came on. I turned on the switch and checked the dash side of the wiring at that connector with a VOM..... no power at the black wire. I had already checked the fuse and it was good, so after opening up the face of the instrument cluster, I unplugged the switch and checked the pink wire and once again, no power, but the connector was loose in the plug body, so after extracting it, I tightened it up, put it back in and now the lights work! I probably worked it loose when I installed the Christmas stereo from my kids. At 6'3+" and 270 lbs, I have a tough time working on a dash in the car, even with the driver's seat out. The Rallye dash light bar still doesn't work, but that is more than likely a switch problem I will solve with a jumper wire. Thanks for the help Eddie and Dave!

by **dave-r** » 08 Apr 2007 9:12

Glad you found the problem Jack.

You know. Between your Challenger and Eddies I can't make up my mind which car I like best.

It is for sure one or the other.

by **Eddie** » 08 Apr 2007 15:19

Good to hear it Jack. Man you are a big man, bet you weren't looking forward to getting under there. You should be complimented on your diagnostic skills. :thumbsup:

by **dave-r** » 08 Apr 2007 16:27

Jack has got a good sense of logic that's for sure. :s017:

by **JackT** » 08 Apr 2007 16:58

I really like Eddie's car..... that N96 on a Challenger fender tag and the original shaker are really rare items and the quality of the work on it is great! As for my diagnostic skills, I had some help by phone from Julius Steuer that got me started down the correct path. When I started this repair, I did not know the headlight switch was a double-pole switch with two power leads to it. Now for that jumper to bypass the dimmer switch..... more to learn.

by **dave-r** » 08 Apr 2007 17:48

I had forgotten about the two power leads. But my switch was toasted inside. It would sometimes go off while driving at night. :shock:

by **Eddie** » 08 Apr 2007 21:32

Dave is that safe? It doesn't create to much heat from the resistance? Oh and thanks for the kind words, just glad Jack got it fixed, his car is sweet, Ol Julius S. is great isnt' he? Didn't he restore Richard Carpenters,(from the music duo "The Carpenters"), his MoPars? He has quite a collection of rare MoPars mostly E-bodies.

by **JackT** » 09 Apr 2007 0:55

I believe Richard Carpenter is one of Julius' clients. The really nice thing this weekend was installing the horns on my GTX..... went like clockwork and they worked perfectly!

by **dave-r** » 09 Apr 2007 8:28

airfuelEddie wrote:Dave is that safe? It doesn't create to much heat from the resistance?

Pay attention Eddie! :lol:

I already said I bought a NOS one from ebay and replaced it. :wink:

by **Eddie** » 09 Apr 2007 15:06

Cool Jack, sorry Dave. :lol:

by **ianandjess** » 10 Apr 2007 11:58

gday guys while were talking lighting trouble ill but in , when i put my high beam on my tail light go out , every thing else works any suggestions?
cheers ian

by **dave-r** » 10 Apr 2007 13:00

It's haunted! :s008:

by **ianandjess** » 10 Apr 2007 13:30

yep i think your right dave :lol:

by **Eddie** » 10 Apr 2007 15:41

Is it the floor mounted, foot operated?

by **spitfire9137** » 10 Apr 2007 21:29

airfuelEddie wrote:Is it the floor mounted, foot operated?

Don't think it was offered any other way...

by **spitfire9137** » 10 Apr 2007 21:45

Looking at my wiring diagrams for a 73, it looks like the only thing it could be is the headlight switch shorting out when you apply the high beams and draw more power. Are they stock head lights or aftermarkets?

by **Eddie** » 10 Apr 2007 21:46

I would remove it and start there. Try a re-pop or a used one.

by **spitfire9137** » 10 Apr 2007 22:43

Also do the panel lights still work when the high beams are on or do they go out with the tail lights?

by **Eddie** » 11 Apr 2007 14:20

According to the wiring diagram, they are connected in series with the taillights. Bet your switch is corroded or the contacts are shorting to ground, then the taillights would be off. I would remove the switch, one screw, two,(2) wire lead,(if memory serves me) clean it, or replace it. Let us know! :mrgreen:

by **ianandjess** » 13 Apr 2007 13:54

thanks guys ill check it out & let you know if it works
cheers ian

Re: Light problem