Headlight Wiring Help

[truckster]

I'm just finishing up rewiring my Blazer - yeah, I know, I should have gone with AAW, but I didn't. I saved money and used the EZ Wiring 21 circuit harness. I'm a little stuck on the headlight wiring. The first image is from the EZ Wiring manual - it shows a jumper for the power leads.

The second image is the headlight harness from my Blazer. I jumpered from the red wire to the green wire - the 72 wiring harness shows the green wire coming from the fuse box. The headlights work, but the other lights don't. The headlight switch seemed to be getting really warm, too. I only had it one for about 30 seconds.

Any help would be appreciated.

[VetteVet]

Your first picture looks like a switch for the pre-67 to 72 trucks I think blazers
are same. Your harness plug matches the 68 to 72 trucks. I am trying to load a picture but windows 10 don't want to co-operate.

Here's a link to the picture.

http://www.67-72chevytrucks.com/vboa...5&d=1601382049

It will show you the newer switch which is what you need. The wire colors and what they go to are explained in the pic. The orange wire (top lright) powers the dome/courtesy lights and the two brown wires which are the park/tail lights. There's a jumper on the terminal so that the parking lights stay on when the switch is pulled all the way out.

The blue wire in the center is for the headlights and it goes to the dimmer switch. It may have a stripe with the blue or it may be solid blue.

The dark green wire, left center is for the instrument lights. It is also powered by the orange wire. It runs to the switch rheostat for dash light dimming. and then to the fuse panel to the inst lts fuse holder. A gray wire from the fuse goes to the dash cluster plug to terminal 8 if you have a gauge dash.

Below that is the Red wire from the main power which only powers the blue headlights wire. Contrary to popular belief. A different red power wire runs to the fuse panel and powers the orange wire which goes to the headlight switch and others.

Last is the bottom right dome and courtesy lights terminal which is grounded for those, and it allows the dome light and courtesy lights to come on when the HL switch knob is turned fully clockwise.

[MAC71Cheyenne]

Would also be a good time to add relays to power your headlights. Vettevet has a good write up in the electrical forums for it. Fairly simple and inexpensive. Will take out a lot of the load off the headlight switch and works great. You won't have melted contacts on the switch, especially if there is any additional load. If I can do it anyone can.

[truckster]

Thanks. I knew you would have an answer. I'm at work right now, but I think that's how my switch is laid out, but the wiring diagram (such as it is) from EZ is really confusing. I can't really recommend them to anyone, and I wish I had spent the extra money to get an AAW kit.

I'll try rewiring according to your picture when I get home tonight and let you know how it works.

Thanks again.

[MikeB]

There's always good info and diagrams in AAW installation instructions: https://smhttp-ssl-87263.nexcesscdn....d_Design_1.pdf

And here are the instructions for the Painless kit for 67-72 trucks. https://www.painlessperformance.com/Manuals/10206.pdf

Hopefully you can get a little help from each one.

[truckster]

Thanks. That diagram really helped out.

Mac71 - I installed the headlight relay up front. My problem was with EZ Wiring's diagram foe the switch - it was totally off. The factory truck wiring diagram isn't very detailed in the area of the switch, so I really appreciate VetteVet's help, as well as everyone else who chimed in.