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OKGMC
April 19th, 2014, 11:00 PM
Does anyone have a good lead on a replacement wiring harness for a 65? I found the buckets and most of the rest of the hardware so from that aspect I'm good. I see lots of single light Chevy type, but no dual headlight models. Is it possible to maybe back up a few years and get an earlier model harness?

BarryGMC
April 20th, 2014, 04:22 AM
Shoot me a pm. I have about 20 .

kieth
April 22nd, 2014, 05:19 PM
Does anyone have a good lead on a replacement wiring harness for a 65? I found the buckets and most of the rest of the hardware so from that aspect I'm good. I see lots of single light Chevy type, but no dual headlight models. Is it possible to maybe back up a few years and get an earlier model harness?


After you find your harness for dual headlights be sure and wire it with relays instead of directly through the dash switch, your lights will be a lot brighter and you will not believe how much better you can see at night......Kieth:woo::ahhhh:

aphaynes
April 22nd, 2014, 05:31 PM
After you find your harness for dual headlights be sure and wire it with relays instead of directly through the dash switch, your lights will be a lot brighter and you will not believe how much better you can see at night......Kieth:woo::ahhhh:

Interesting. What type of relays did you use?

kieth
April 22nd, 2014, 08:35 PM
Interesting. What type of relays did you use?

standard bosch or any brand 30 amp relays.........What you do is wire the relays directly to the battery with a 20 amp fuse on each one. Then wire the trigger wire to the wire that comes from your headlight circuit. This keeps the headlight circuit from seeing those heavy current draws......Kieth

OKGMC
April 26th, 2014, 04:56 PM
Thanks for the relay advice, I will be adding them into my headlight wiring plan.

weeniewawa
April 26th, 2014, 11:01 PM
you can do a search for relays and wiring for your situation but here is a diagram, there are lots more out there, this one is not labeled as good as others but you get the idea


http://www.rowand.net/Shop/Tech/images/HeadlightRelayWiringDiagram.jpg

Irishbleueyes
April 27th, 2014, 05:41 PM
http://6066gmcguy.com/ Scroll down to the bottom its under headlight system in electrical

BarryGMC
May 7th, 2014, 11:52 PM
Glad you got the harness. Your signal problem is most likely in the turn signal switch.

OKGMC
May 11th, 2014, 04:00 PM
Found the self-inflicted signal problem. When I was working with the wiring (main plug on the back of the dash cluster), I inadvertently swapped two wires. In the end, all is well. I now know what shape my wiring is in and have new wiring in place in the areas that needed it. Glad to be back on the road again. Time to find some relays to improve the headlight system. Everyone, thanks for the help and parts support.

aphaynes
June 2nd, 2014, 04:55 PM
you can do a search for relays and wiring for your situation but here is a diagram, there are lots more out there, this one is not labeled as good as others but you get the idea


http://www.rowand.net/Shop/Tech/images/HeadlightRelayWiringDiagram.jpg

I decided to implement this wiring scheme this weekend. After getting it all done, the sun was down so good time to test it. One high beam was not coming on while the other was nice and bright and one low beam was dimmer than the other. At first I was thinking "what did I wire wrong?" :runforthehills:, but then I assumed it couldn't be the relay wiring or, in the case of the high beams, neither would work right. So, I was thinking grounding or something. Yes, I already had some issues prior to implementing the relays, so I figured while implementing this scheme I could figure out what the issues were.

So, the next day, when I had sunlight again, I started removing the headlight bezels. As I pulled them off and one of the lo beams flopped out, dangling by it's connector wires, I realized the 49 year old plastic adjusters were all pretty shot; either completely broke or cracked pretty good on all the lights. :(

Ok, back to wiring. Got my meter out to start trouble shooting, turned on the lights, and when I grabbed the dangling lo beam light that was dim and moved it, it suddenly brightened up. As I moved it around it fluctuated from dim to bright. I figured, the contacts in the connector must just be dirty....and they were. However, cleaning them did not solve the issue. As I held the connector and squeezed it, the light brightness would again fluctuate from dim to bright. I assume the connector is just stretched/sprung/worn out from being so old. I repeated the process for all of the lights to find the same results. Even the Hi beam that was off came right on when squeezing it's connector. So, relay wiring good...all connectors worn out. Once I replace them, all should be nice and bright again. :thumbsup: