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TR6 TR-6 with one dim head light?

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mabbott

mabbott

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Hi, I could use some assistance with this one. I have a 73 TR6 that has one very dim head light on the drivers side. It's not a defective bulb.

Here is what I have observeed so far:
- Switched the drivers side and passanger side head lights and the the problem is still present.

- On the passenger side (that works)the bulb seems warm / hot but I don't have any basis for what it should feel like.

- With both bulbs removed and then plugging in the passenger bulb the light goes on.

- With both bulbs removed and then plugging in the drivers side (dim side)the light DOESN'T turn on.

- The voltage at the three prong plug behind the bulbs is 13+ volts.

Any ideas? Ground issue? Where to look?

Thanks,
Mark
 
Yup, the driver's side bulb is not getting grounded. It lights dimly because current is flowing through both of it's filaments in series, then through the other filament on the other side.

One way to check is to plug the bulb into the socket and then check the voltages (piercing the insulation if you can't get to the contact from behind the socket).
 
Thanks for the responses....

Where to look?
Any idea on where the BLK Ground wire goes from the head light socket/plug?
- Into a harness?
- To a screw or spade local to the head light bucket?
 
I had the exact thing happen to me at the beginning of the season... drivers headlight (low beam) would not come on.
I bought a new bulb thinking it was bad. When I installed the new one... same thing!
I did just what Andy said and found it was a bullet connector at the front of the car that runs across in front of the radiator. Once I cleaned it, I was good to go!!!
 
The front ground is in the middle behind the grill
About here
DSCF3716.jpg
 
Hi all, Had the same problem on a TR4A, cleaned the Bullets and some what better, changed to alternator, better still, got the heavy duty wiring harness from VB and now have excellent lights. Halogen bulbs also. This is not a plug and play wiring harness but with a few changes it looks great, Come off the solenoid and put in a double fuse box from your local auto supply on the under side of the inside fender well next to the voltage regulator and you can run with your wiring harness. Mount the two relays next to the passenger side horn. They didn't made it to go through the hole in the light bell, so cut and solder them back together. I didn't like to do that but a necessary evil. It is a good harness and you can't make it up for $30.


Wayne
 
Gentlemen, with all your input I have resolved the issue. I tested the bad ground suggestions by using a clip lead to the GND prong on the head light and touching it to a ground.....and the light went bright! I followed the lead in the harness to the area under the radiator shroud. After gaing access I found that the bullet terminal had worked its way loose.

Thanks to all the contributed, its a great group of knowledgeable people here.
 
Further to Wayne's post, I have seen headlight wiring harnesses with relays from several suppliers. Prices range from ~$30 to ~$150. Just curious if anyone can speak to the wide difference in prices. It's just some wires and a couple of relays, right?

Bob
 
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