Wedge TR8 Headlight/Electrical Problem

[RSMTR8]

OK, here is the deal. The car is running great. But when I drive at night, that is another story. Here is what happened tonight. I start the car, then turn the headlight switch on, and the headligts "dance" for like 25 - 30 seconds, and just when you think they are going to disco the night away, they finally stay up! But the car tried to die, I stayed on the gas for a minute or 2, and then it stopped trying to die. So I began to drive home, and everything was fine, I then noticed that the clock on my radio had reset, and all the radio station that were programed were gone. That definetlyt happened durig the startup electrical deal. I was almost home, when I hit a small bump in the road, and what do you know the light when out, and the headlight danced again for like 15 seconds. All the lights went out breifly, dash lights and all! So where do I begin?! I know my realys are good, replaced them about 3 months ago. The switch is also brand new. Oh, here is the other odd thing. If the car is NOT running, and you turn on the headlights, the passanger side goes up, then 2 seconds later, the drivers side goes up, and they stay up!, no big dance. So whats the deal only when the car is running, do they go disco on me! HELP! I have checked and re checked all my grounds. I even added one per suggestion from someone here in the fourm to the rear passenger side lights where there is a connector. I have replaced the battery terminals on the battery as well. I also recently replaced the alternator with a lucas 85A unit, but I had all these problems before the new alternator.



Thanks,

Rod

 

[Mickey Richaud]

That's a good 'un you got there, Rod!

Even though you checked all your grounds, that's a usual suspect. The headlight motors themselves are pretty stout, so I'd recheck all connections.

Good luck!

Mickey

 

[RSMTR8]

I have checked them several times, at least the 2 in the engine compartment, and the one in the trunk from the battery. ANY others that might effect the lights?!


Rod

 

[swift6]

There should also be a ground between the engine and the body, near the starter. Thick braided wire type. I've been told that this is also a very important ground area.

 

[RSMTR8]

Do you know if it can be seen from the top, or does the car have to be on lift to see that ground?


Thanks!

Rod

 

[tr8todd]

It's starting to sound like it could be the main power feed to the fuse box,(large brown wire) or possibly the ignition switch. When the headlights are cycling up and down, they draw alot of current. If there is a weak link in the path of the current flow, the relays may not get the signal to stop cycling. The whole headlight lifting proceedure is complicated. There are several things that need to happen in order for it to go right. You might want to check the terminal on the passenger firewall where the power cable transitions from the engine compartment to the cable that travels to the rear of the car. I would also lubricate the headlight mechanisms. This won't solve your problem, but should be done now that your thinking about your headlights. There is also a ground in behind your center consule that I have seen cause problems. I have also seen the installation of after market stereos where the power was pulled from a wire that it shouln't have been. It is highly probable that you have more than one issue here. Electrical contact issues are very sporatic and lead to all kinds of symptoms. Sounds like it's time to spend some quality time with your test light, emery cloth and electrical contact grease. British cars don't like to sit. Sitting is what leads to all of those electrical and hydraulic issues. The moving parts need to move in order to prevent corrosion.

 

[philman]

could you have two different problems? I just went through the headlamp ckt in my '76 fhc. cleaned up the brushes/commutator and replaced the headlamp limit switch (supposedly a bad diode will cause cycling). now the headlamp snaps into place as it should (the sound of the headlamp up latch) without cycling up and down until it decides to stop. i think the problem in my case was the brushes were corroded -- i suppose i should have replaced them.

 

[philman]

p.s. my headlamps had the same symptom where without the engine running the seemed to work fine. maybe the alternator puts out a higher voltage causing the d.c. motor to work faster!? making the cycle end signal to the headlamp relay too short for the relay to react to? I also replaced the headlamp relays with new mechanical ones -- I had been using solid state relays.

 

[RSMTR8]

Here is what I know for sure, when the car is completly off, no key or anything the lights will not go up, and you can hear the relays making a lot of noise (I have replaced these twice!). Then, actually start the car, and the drivers side goes up, then the passenger side, then the drivers side, and passenger side again, and then they stay up. While this dance is goin on, the RADIO goes haywire, it goes out, and comes back on when the dance stops, and the time and channels have been reset! Then while the car is still running, turn the lights off, and after about 10 - 15 seconds of up down, up down, and the radio going nuts they stay down! I took the car over to ACME Auto Electric here in town, and the mechanic said he could for sure fix it, but he would need the wiring diagram to the car. I think Wedge Parts has this diagram for sale. So I think once the weather turnS completly cold here I am going to take it to them, and let them have a go at it! As far as the ignition being the problem, how would you test that, as the car starts fine.


Thanks!


Rod

 

[RSMTR8]

The ground behind the center console is located EXACTLY where? I have checked the 3 under the hood. (1 behind each head light, and another one behind that on the passenger side, and the truk ground from the main battery, all good. I have also looked at the main wires near the passenger side floor, there are 3 wire, 2 large brown, and 1 thin brown. The only one that looked suspect was the thin brown one, which I believe goes to the alternator, but as I have an aftermarket alternator (Lucas 85A), I do not believe that thin wire is even hooked up. Keep the suggestions coming!


Thanks!


Rod

 

[tr8todd]

There is about five ground wires that bolt to the body next to the fuse box. You might be able to see them under the glove box area. There are also grounds where the headlight wires plug together. Those grounds are always suspect. The ones on the driver's side are tough to get at if you have A/C relays in the way. If you still need a wiring diagram, contact me and I can fax one over to you. Provided it shows up well enough on my printer/photo copier. There are W/Ds in the back of the factory shop manual. I am required to have one with me by the SCCA whenever I race, in case someone files a protest against my car.

 

[RSMTR8]

Yes, the ones that plug togther near the headlights inside the engine compartment I have checked............In the glove box, I have not. My car does not have A/C, never did.

Thanks!