help me please

[big dan]

I need some help getting my headlights and tail lights to work. Im not very good at figuring out wiring problems and have tried following wiring diagrams to find where problem areas might be but dont really understand the diagram.

So here is what Ive checked: bulbs are good, tried a new switch, checked all the wires to make sure they were connected and checked all the fuses. all my signal lights and brake lights work. Ive used a test light to see if I was getting power to the bulbs and there is no power at the bulb sockets.

are there any other common problem areas that I could check before I start digging through all the wires? thanks

 

[supersize75k5]

A few things.. i check with lights..


1. check to see if you are getting power to the fuse

2. check to see if your dimmer switch has power

3. if the top two check out ok and have power..then go wiggle the wiring harness on the engin bay side..

4. if that does not work, take the 4 wires where they come out the firewall and head to the back of the truck and check those 4 wires fow power, also check the wires condition all the way back, exhaust/time/rust/ bad luck can fray or ruin a wire.

5. if those 4 wires check out as working, then head to the back and check the ground wires behind the tail llight support.

6. if still no luck, check for power going to your break light switch,


a real common problem is the ground wires with head lights and tail lights.

good luck i have delt with this same issue on a few trucks

 

[big dan]

thanks, thats just what I was looking for but raised another question.

if the dimmer switch was bad could it cause the tail lights to not work also?

I swapped this column out of another truck and I know that the dimmer switch will not switch from high to low, stays on low all the time, but the lights did work.

 

[chevy wrangler]

i have the same problem but my lights turn off when the dimmer switch is turned off

 

[tRustyK5]

Back probe both the dimmer switch and the headlight switch for power. If you find power at the headlight switch pull the switch out for the courtesy lights and back probe again to see where the power is being routed. pull it out once more and repeat for the headlight circuit. With the headlight switch on there should be power to the dimmer switch.

Bad dimmer switches are a common cause of "no lights". A bad headlight switch seems more likely though. I spent an entire day tracing wires and checking circuits on a Jeep Comanche pick-up (GM column and headlight switch). It had many of the same symptoms and I eventually narrowed it down to the switch. We chucked in a spare we had laying around and all the crap that wasn't working began working again.

Rene

 

[chevy wrangler]

its a 74 and has new dimmer switch and light switch

 

[supersize75k5]

sometimes you replace a part with a new but bad part,..



Ive had my share of headaches from bran new parts that did not work.. i think the only thing worse than not being a ble to find the problem is finding out later that you indeed did replace the problem but with a bran new bad defective part..

test light is your friend

 

[BIG*RED]

I just had a similar problem with my blazer saturday morning..tuned out to be the dimmer switch

 

[big dan]

test light is your friend

yup just got one yesterday. never had one but I figured now would be a good time. so looks like Ill be doing a little search and find with the test light later.

 

[big dan]

ok I have no power going to my headlight switch. still havent checked to see if I have power at the fuse. my fuse box has no markings to tell which one is for the lights but Ive pulled them and they all look good. any more ideas? thanks