Some wiring troubles here...

Okay. We tested the electrical in the GS last night and some things were just dandy and some... not so great. The car has a Painless 18-circuit harness, LED lights with electronic flashers and an Ididit steering column. The problems we're having comes as a surprise to me since everything seemed so logical as it was installed. We really didn't expect any problems (which is probably why we have them).

The headlights work.
The high beams work.
The front parking lights work (but go off when headlights are on)
The rear parking lights work.
The brake lights work.
The interior and courtesty lights work.
The instrument cluster lights work.
Power windows work.
Ignition switch sends power to the starter.

So far so good... but

The wipers do not work. Nothing happens. This is a factory '63 Corvette wiper switch and motor so you'd think it would be simple. The Painless book had no diagrams for the wipers for some reason so we're not sure if they're wired properly.

The turn signals don't work. They go on but don't blink. When on, the rear bulb lights but not as bright as it should be (it should be as bright as a brake light but actually looks dimmer than the rear parking lights) and the front bulb barely lights up at all. Anyone have any ideas or things we should check?

Strange brake light problem. The brake lights glow ever so slightly (barly visible) only when the ignition is in the 'on' position. We tried to isolate it and diconnected the brake switch but they still stayed on. They only go completely off when the ignition switch is turned off. This one really confuses us because the tail light wiring is so simple. Any ideas?

HELP!!

 

I think you better check the GROUND circuits first, youve got something feeding-back into the light circuits in search of a ground path.

 

That's what some guys at the corvetteforum are saying too. We'll definately look into the ground for the brake lights.

Anyone else care to contribute? Keep the ideas coming! I need a flood of things to try. I really want to get past this latest "challenge" quickly.

 

The ground problem may not be in the brake light circuit, but rather in another one that shares the same fuse or relay pull or whatever.

If another circuit has a bad ground, but your brake light circuit has a good ground, current will flow to it via any available path.

 

Interesting read on the grounding, but, if the parking bulbs, turn signal bulbs and the brake bulbs all share the exact same ground why would only the brake lights illuminate?

Also, heres another one that baffles me, why does the OEM ignition switch have a ground?s

 

That's exactly why I directed to check the other grounds.

Those devices may share the same ground, but they're switched separately. Each of those with electromechanical switches has a control circuit...with a ground...

 

i had the same problem with a powder coated tube chassis race car that i am wiring. it was the grounds.

 

I'm not much help on the wiring although my 64' corvette had similar wire problems but It was simple stuff like the flasher caused the blinkers to light up an stay on. The flasher was bad and one of the bulb sockets in the rear was causing problems because I was having trouble keeping it grounded. Does your wiper motor bench test ok? Mine had a bad armature and brushes in it. It wouldn't do anything when I hooked it to a battery. How clean is your fuse block? Or maybe you don't even have a std. fuse block anymore? Mine had the contacts kinda crusty and it caused all kinds of little gremilins for a while. Even though a new fuse was popped in it was still causing contact problems. My 64' was a nightmare car that I sold a couple weeks ago. It left such a bad taste in my mouth that I can't stand to look at a corvette anymore. I would like to see all corvettes loaded upon a sea barge and shoved into the ocean. Just kidding but I hope you get the wiring figured out. I sure pulled my hair out for a while and still had a couple wire issues when I sold it.

 

I used the 18 circuit painless setup as well. Do you have seperate bulbs for the brake lights, directionals and parking lights? There are seperate wiring diagrams if you have dual filiment bulbs or single filiment ones.
Check your flasher relays. You may have the 4 way switched with the directional.
I also used the generic wiper washer switch that painless sells as well as the 4 way headlight switch. Made the wiring a lot simpler versus grafting onto the OEM BMW setup.
It doesn't sound like a bad ground to me, more like incorrect wiring.
The interpaly between the parling, brake, directional and 4-way flasher circuits are tricky.

 

Well found the possible, issue with the brake lights remaining dimly on when the ignition was in the "on" position. The cruise control ? . . . on the module that Mark got, out of a 4th gen Camaro, was labeled with a wire to go to the N/O terminal, disconnect the wire and the brake lights go back to normal.

As for the turn signals, I have to assume the "load" is the problem with LED's, should test some normal bulbs and then work backwards.

So far no bad grounds.

The Corvette wiper motor is weird. The switch controls the grounding, not the power, plus go figure, there were three more terminals hiding that I never saw, so I beleive that one is on the mend.

Thanks for all the feed back all.

 

The lights are dual element LED's. We have it wired so that all four "lights" illuminate as the parking lights, the inner two are wired as the brake lights and the outer two wired as turn signals, as far as I can tell the wiring is doen correctly per Painless'es diagram, for the dual element bulbs, I feel the "load" is now the problem which I assumed electronic flashers would fix as it did in my 2000 Camaro, but must be wrong thinking.

 

If you have LED taillights you are probably not drawing enough current to trigger the normal thermal flasher. You can use an LED flasher or wire in a resistor to increase the load. Call Painless Tech Support at 800 423 9696 they can explain both options to you. Yes, I work for Painless.

As far as the other issues you mention I would say definiitely call the Tech Support Hotline. We have 4 guys sitting there waiting on your call. They ain't pretty but they can help.

 

as far as the parking lights going out when the **** is pulled all the way out. That is the way the harnesses are designed due to government regulations they want to see a definite on/off flasher of amber from on coming traffic so we design our harnesses to have the parking lights go off when the **** is all the way out. you can splice the #927 (parklights) in with the #929 (taillights) and they will stay on like they did from the factory. and yes sir if you are using LED bilbs you need 2 no-load flashers installed in out fuse box for everything to operate properly.