low voltage at taillights

[flyinlow]

Working on a'70 taillights . Got the lightbulb problem resolved with all new bulbs , however the taillights are still dim. Checked the voltage with the parking lights on, a battery charger on the battery.  12.7 volts and slowly raising at the battery. 10.7 at the taillight socket. If you jumper from the battery to the taillights they brighten noticeably.

Any common trouble spots?

[Plumcrazy]

There's a flat I think 6 way electrical connector by the parking brake pedal for all the rear lights. Check there first.

[flyinlow]

There's a flat I think 6 way electrical connector by the parking brake pedal for all the rear lights. Check there first.

Thanks, I will try to check that tonight.

[nascarxx29]

Check the rear body harness connector check it and the route of wires going under rocker sills under backseat to trunk.For damage etc
Another possible cause of dim tail light is grounds.I have to use jumper wires on 70 RR
Also check sockets remove bulb and look for frayed/ rubbed through wires.

[elacruze]

Try this-use a jumper between the taillight housing and a good body ground. If the lights brighten when you improve their ground, you only have to secure the ground at the housing.

[Plumcrazy]

Try this-use a jumper between the taillight housing and a good body ground. If the lights brighten when you improve their ground, you only have to secure the ground at the housing.

I don't think it's a ground problem. He says the lights brighten noticeably if he runs a wire from the battery to the tail lights

[elacruze]

Try this-use a jumper between the taillight housing and a good body ground. If the lights brighten when you improve their ground, you only have to secure the ground at the housing.

I don't think it's a ground problem. He says the lights brighten noticeably if he runs a wire from the battery to the tail lights

Never forget that the ground side of a load is part of the circuit and exactly as important as the power side.

<edit>

oops, right. It's late.

Disconnect and reconnect each connector from rear to front until it gets better.

[Chryco Psycho]

with a measured voltage drop at the lights it has to be a resistance in the power feed somewhere between the headlight switch & taillights so check all the connectors end to end clean all the connectors & use di-electric grease to minimize corrosion in the future .