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MG MGB Technical - Electrical problem MGB 79

I have an electrical problem on a 79 US- specification V8 Rover Vitesse conversion MGB.
The car runs and starts but the following functions are out.
*turn signals, brake light, internal fan, wipers.
All of these functions are working very slowly or weakly when the car is cranking on the starter. As soon as the cranking stops the functions are out again. The turn signals never comes on.
The second fuse from the bottom, white or white/brown on the inbound terminal and green on the outbound terminal does not have electrical flow.
There are minimal changes made electrically when converting to V8. I have bypassed the resistor white/green wire powering the coil substituting it with the white cable located nearby as per recommendations on this site.
These symptoms are new after a brisk drive in the snow during subzero temperatures. Before this it has run perfectly for many years.

Thanks in advance

Erik
Erik Kallstrom

Erik. Check for power into the fuse box. If you have power, check for power on the little clip which holds the fuse. If power there, check for power on the fuse end which fits into that clip. If there is power on the metal section of the fuse (front--power in), check for power at the metal section of the fuse (rear--power output). If there is power there, check for power on the clip itself. If there is power on the clip, check the spade terminal at the rear of the fuse box for power. If there is power there, you have a problem somewhere in the green wire circuit and will have to trace it forwards to find out where the loss is.

Most common problem is that the clips that hold the fuse become corroded and power does not flow through the fuse and to the green circuit. If this is the case, remove the fuse and clean the insides of the clip with a small, round brush or with a piece of emery cloth wrapped around a small stick. Very common problem, even here in Arizona were things are, mostly, dry.

Les
Les Bengtson

Please, put htis thread on hold for a moment as i found a similar thread in the archive.

Cheers
Erik
Erik Kallstrom

Probably different from the other thread given the different symptoms. Is the ignition relay clicking when you turn the ignition on and off? If not then check the white circuit from the ignition switch, through the connector by the steering column, to the relay for 12v with the key on. Check the black wire, if that shows 12v then the earth to the body nearby is bad. If that's OK check the brown and white/brown wires for 12v. On the brown but not the white/brown is a bad relay. No 12v on the brown shows a bad connection back towards the solenoid, and both these last two can be the cause if the relay *is* clicking.

If you have 12v on the white/brown at the relay then Les is there or thereabouts, i.e. either power is not getting from the white/brown connector from the ignition relay onto its fusebox spade, or from there to that end of the fuse holder (rivetted connection on the back), or from there to the end-cap of the fuse, or through the fuse, and the similar connections from there to the green wire connectors.
P Hunt

Thank you Paul and Les,

Problem solved! It was the ignition relay.

Erik
Erik Kallstrom

Good-oh.
P Hunt

This thread was discussed between 24/01/2010 and 26/01/2010

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