no turn signals. brake lights dim

[lengryske]

We have no turn signals... we do have hazards... the barek lights are very dim . It seems like a grouding issue but I cannot loacte the problem. Any advice is appreciated.
Thanks, Len

[KimMG]

First you need to make sure you are getting power to the lamps.
You may also have two separate problems.

Common problem:
The turn signals and brake lights have a common power source, the third fuse. Is there anything else not working?

Turn signals:
Since the hazards are working, the grounds must be ok. Hazard lights get power from the brown wire circuit, whereas the turn signals get power from the green wire circuit.
Someone else recently had the same problem. Some trouble shooting steps can be found in the following thread.
http://www.mgexperience.net/phorum/r...271#msg-751271

Brake lights:
Have you checked for power to the sockets? Have you checked the input and output of the brake light switch? High resistant connections can cause voltage drops. The following thread shows that a failing brake light switch caused the problem. http://www.mgexperience.net/phorum/r...595#msg-728595

Wiring diagrams are available at http://www.advanceautowire.com click on stock schematics.
You will need a copy of the wiring diagram and a meter or test light to correctly diagnos the fault.
In the future, please include the model year when requesting assistance. Not all Bs are wired the same.

[lengryske]

I do believe this may be a ground problem. We have found one wire and grounded it and now the turn signals work but are very dim. Prior to this there was no signal at all either on the dash or at the lights themselves.
Where would the primary ground points be?

[KimMG]

Do you have a multimeter?
What color was the wire you connected to ground?
If you looked at the wiring diagram, you would have noticed that the hazards and the turn signals use the same bulbs, grounds and much of the wiring.

In some years the grounding point for the rear is located inside of the trunk and secured with one of the license plate screws. The grounds for the tail lights can also be done through the housings. After years, due to corrosion, the housings won't provide a good ground, so you may have to attach ground wires to the bulb sockets.

After cleaning a connection, apply dielectric grease to prevent future corrosion.

[barefootcontessain]

Originally Posted by lengryske

We have no turn signals... we do have hazards... the barek lights are very dim . It seems like a grouding issue but I cannot loacte the problem. Any advice is appreciated.
Thanks, Len

Len look in the trunk, bent over, and up inside to your right. There is a cannister there and when the hoses are cracked or missing you have to replace them as they have something to do with the lights also. The cannister is emission exhaust stuff and there should be 2 hoses; 1 from tank to cannister and 1 from cannister to fuel pump located in the front right corner of the trunk compartment.
Heather

[KimMG]

Originally Posted by barefootcontessain

Len look in the trunk, bent over, and up inside to your right. There is a cannister there and when the hoses are cracked or missing you have to replace them as they have something to do with the lights also. The cannister is emission exhaust stuff and there should be 2 hoses; 1 from tank to cannister and 1 from cannister to fuel pump located in the front right corner of the trunk compartment.
Heather

The vapor separator in the trunk has nothing to do with the lights. It is not connected to the fuel pump. The vapor separator is a condenser separating fuel vapor from liquid fuel in the fuel tank vent line. Vapors go to the charcoal cannister located in the engine compartment, and the liquid drains back into the tank. If the lines to the vapor separator are damaged or missing, then the trunk can start smelling like gasoline.

The vent line for the fuel pump does not contain fuel vapors and does not connect to the fuel tank vent line. The vent line for the fuel pump is less than 1/8" I.D. and vents into the trunk to help prevent dirt and water from getting into the fuel pump.

[mre64]

I had a similar with my 79 MGB. I replaced the fuse box. You can order the original fuse box from Victoria British, the are relatively cheap and easy to replace. My old fuse box was corroded behind the terminals. I have not a had problem at all since I replaced the fuse box. Also, make sure there is a good ground strap between the engine and the frame, you do not want the engine grounding through the accelerator cable.

Good luck

[paul J]

Originally Posted by barefootcontessain

Len look in the trunk, bent over, and up inside to your right. There is a cannister there and when the hoses are cracked or missing you have to replace them as they have something to do with the lights also. The cannister is emission exhaust stuff and there should be 2 hoses; 1 from tank to cannister and 1 from cannister to fuel pump located in the front right corner of the trunk compartment.
Heather

I know nothing about MGBs!