c10 66 breaklights
 

Hello


1966 c10

I'm looking for some assistance here. I cant seem to get my tail lights to work.. When I turn the headlights on both tail lights work, but the brake lights don't on either side. The drive side was working then stopped and now neither side work. Not sure what the issue could be, so if you have any suggestions please let me know.


Thanks

Re: c10 66 breaklights
 

Brake light circuit goes through the turn signal switch. Do either of the turn signals work in back?

Re: c10 66 breaklights
 

When things are intermittent with electrical, it's usually a connection issue (power OR ground).

When things are possessed by the Devil, it's usually a grounding issue (something is grounding through a different circuit).

Re: c10 66 breaklights
 

I just bought the truck and it doesn't have turn signals. The driver side brake was working but the passenger side was never working. I know my dad was messing with the turn signals in the truck, maybe that caused the one brake light to go out. I'll mess around the turn signals this weekend and see if that does anything.

Thanks

Re: c10 66 breaklights
 

Just asking.. Did you check the bulbs? Sometimes they can look good but not work.

Re: c10 66 breaklights
 

Per your post, it's just the brake lights that are not working. Helpful to have second person to assist you while you test.

1.Double check the bulbs, if you have known good spares, swap them out to verify it's NOT the bulbs
2.There is a brake light switch on the brake pedal lever (up under the dash) check to ensure it is engaging properly, there is adjustment built into that switch. If you have a known good spare, swap them out to verify the switch is not the issue
3.Per user Arne, verify that your turn signals are/are not working
4.Do a visual on the tail light housing, socket and wiring. You need a good ground at the housing for the taillights/brake lights to function properly. Sometimes it's a loose socket, wire or bad ground.

Keep us posted once you have had a chance to check per the suggestions from members in this thread.

Re: c10 66 breaklights
 

the 1st thing i did was replace the bulb...

My dad was thinking it might be the brake light switch, i have to take a look this weekend. Thanks for the feedback.

Re: c10 66 breaklights
 

Great! keep at it and you'll get it figured out. The members in this forum are a great resource for help along the way.

Re: c10 66 breaklights
 

I've posted this before, but here's how I got my brake lights to work properly:
- removed the lenses, removed the buckets
- added a ground from bucket to bed
- added a ground from bed to frame at back
- added a ground from bed to frame at front of bed
- added a ground from back of cab to frame
- added a ground from front of bed to cab

Brake lights work perfectly now. Before, one worked dimly, and one only had "lights on", no brake illumination.

Re: c10 66 breaklights
 

That's a lot of grounds... Would the tail light work and no brake lights if it was a ground issue?


Thanks

Re: c10 66 breaklights
 

Yes, a dirty ground, bad ground can result in having running lights (and most likely dim at that) and no brake lights. The bulb socket grounds itself to the housing which then has a ground wire to frame or body or both. It's important to make sure the bulb socket is tight and secure in the housing, if it's loose (turns freely), it will result in intermittent issues as well. Be sure to check all these things on both tail lights. Clean your ground surfaces really well if they are already in place.

Re: c10 66 breaklights
 

Thank for the feedback. Wont get a chance till next week, but ill keep you guys updated.

Re: c10 66 breaklights
 

Ok so I finally got time to mess with my brake lights. It looks like the issue is with the Taillight Pigtail connector. I'm now just going to upgrade to LED tail lights. My question is what led tail lights do you guys recommend?

Also I noticed I have 3 wires running to the brake light but all the LED lights only have 2...
Thanks

Re: c10 66 breaklights
 

I went led with mine.
United pacific is what i used. There is 3 wires coming from module but still has a 1157 male connector to fit the oe socket.
Since mine never came with the original wiring i did my own wires and used 3 pin deutch connector and did earth directly to frame .
Pic is brake lights on. Nice and bright.
Cheers.
Adriaan.

Re: c10 66 breaklights
 

I used these. (Sorry it's just the package) Simply plug in place of the old ones. No wiring, no mods.

Re: c10 66 breaklights
 

A couple notes: Make sure you get red LED bulbs, not white. (White through a red lens will be rather dim.) And note that you may need to replace the signal flasher relay to an electronic unit if the signals flash very fast.