Does anyone have a factory wiring diagram for the quad headlight setup on an 85 Brat? The crappy Haines manual I found in a junkyard and Alldata don't have a diagram for quad headlights.

 

I have a short between the highbeam and the lowbeam circuit somewhere. The only suggestion I've found on this board was that the high/low switch goes bad, but I just took it apart and verified that there is nothing wrong with the switch.

 

If anyone has a diagram I'd appreciate it. Thanks!

I'm pretty sure it's the same for '84 and I believe I have that manual. If no one else gets it to you before next Tuesday, I'll bring it to work with me and scan the wiring diagram for you and send it off by email. If you still haven't gotten a response by Monday evening, drop me a PM with your email address and I'll remember to take the shop manual to work with me.

Sounds good. Thanks

Define "short".... what's going on exactly?

 

GD

With the headlights on and the switch in the lowbeam position the outer lights highbeams are on, the inner lights are very dim, and the highbeam indicator light is on dimly.

 

With the switch in the highbeam position, the outer light lowbeams are on (possibly dimmer than they should be), the inner lights are lit, and the indicator light is on brighter.

 

The previous owner swapped the outer lights for ones with removable bulbs, so I'm wondering if the pin locations on the bulbs are different than for the stock sealed beams (which would explain the backwards operation of the outer lights), but that doesn't explain why the inners are getting weak voltage in the lowbeam position.

Are the housings for the removeable bulbs made of metal and glass? They probably are..... This is creating the ground needed for the lights to bypass the switch. In the EA81 the lights receive a constant 12v signal and the ground is switched. With metal backed housings the ground goes through the bucket and illuminates the bulbs.

 

GD

Interesting. I'll look into that

If it's non-California (aka no ECU) Here's a (labelled) 84-up Brat/Brumby MV*

 

 

My quad lights kinda does a similar weird dimmy stuff. I kind of like it. LEO might not, however.

About every time I trace down a wire thinking it's frayed somewhere turns out the contacts were corroded or loose. You might be able to scavenge some connections from old harness bits if the light's contacts are fubar. Stuff exposed to weather/grease tend to get erratic.

 

 

*same as another source, but with the part numbers labelled.

I have a pdf of the '83 electrical system. It's not a great one as pages are missing, but it does have the lighting diagram.

 

PM me your email addy and I can send it to you.

File has been sent.

Update:

 

My headlights are fixed. Thanks everyone for your help. Here is what I found:

 

I checked if the aftermarket light housings had any continuity between the bulb terminals and ground (as suggested by GD) and found that they are plastic and had no continuity. Next I unplugged all of the lights and did some testing. I found that the dimly lit highbeam indicator on the dash went out with the lights unplugged. From this I determined that there was no short to ground in the wiring.

 

The H4 bulbs that the new housings take have a different pinout than the stock sealed beam headlights. Once I repinned the headlight connectors everything worked perfect. The current was actually travelling through both filaments, causing the inner lights to light up dimly, the high beam indicator to stay lit, and my "backward" operation of the high/low switch.

Update:

 

My headlights are fixed. Thanks everyone for your help. Here is what I found:

 

I checked if the aftermarket light housings had any continuity between the bulb terminals and ground (as suggested by GD) and found that they are plastic and had no continuity. Next I unplugged all of the lights and did some testing. I found that the dimly lit highbeam indicator on the dash went out with the lights unplugged. From this I determined that there was no short to ground in the wiring.

 

The H4 bulbs that the new housings take have a different pinout than the stock sealed beam headlights. Once I repinned the headlight connectors everything worked perfect. The current was actually travelling through both filaments, causing the inner lights to light up dimly, the high beam indicator to stay lit, and my "backward" operation of the high/low switch.

Good job. Thanks for the follow up explanation. So frustrating to never get a follow up explanation with a successful repair.

Sounds exactly like my problem except i havent replaced my lights, but it does give me an idea. I recently did plasti-dip the retaining rings (the metal rings the hold the lights in place) for the headlights, but didn't do anything to the actual buckets. and if i'm reading right i do need some bare metal to complete the ground. Funny, it worked just fine for about a week after i did it.