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MG MGB Technical - Electrical system

I have a 1980 MGB Limited Edition, 3rd owner. It is my fathers car and he is unable to drive it due to health reasons. It set for a while 3 months and the battery went dead. I started the car up after having to tap on the fuel pump to free the mechanism.

<<<<<< ( I know this is a long story but I need help and think with all the details somebody may be able to help me. )>>>>>>>

During the process of strating the car, and driving it 175 feet,
I lost the fuel guage, reverse lights, headlights, turn signals and the right side only Hazard flashers. The first thing I thought of was a fuse. I found the fusebox under the hood on the right fenderwell, checked then replaced them ALL with brand new fuses, including 2 that were "in-line style" fuses under the fuse box. This did not change anything.
I have since been under the dash on the drivers side of the vehicle trying to see if there were any fuses or wiring arness plugs loose, any loose connections..... and have found nothing.

I live in the country where there are no people who know anything about these cars....... Go figure my luck? The car is in fantastic shape, original condition, cranks right up, purrs like a kitten at idle and roars like a tiger when you accelerate.
I would really like to be able to fix problem so I an take my father for a tour around the backroads.

Any help would be greatly appreciated.
Thank you
W. D. TAYLOR

Best place to start is P. Hunts site,

http://www.mgb-stuff.org.uk/

look under spanners electrics, 1st site to bookmark after this, good luck

Tatty

I would say you have several electrical problems, you will have to get down to ferreting out each of them in turn, but from the sound of things it will be well worth the perseverance.

The gauges, reverse lights and turn signals are powered from the 2nd fuse up in the 4-way fuse box on the right-hand inner wing. Fuse problems are less likely than surface corrosion, but the same corrosion can occur on the fuse holders, the spades and wire connectors, and there is a rivetted connection on the back of the fusebox that can also cause problems.

The headlights are unfused and the most likely cause of any problems are in the bullet connectors right at the front of the car. But if neither dipped nor main beams work, but the headlamp flasher does, then problems in the main lighting switch or dip-switch are indicated.

The hazards *are* fused but the single fuse affects both sides. If only one side is affected again suspect the bullet connectors and again at the the front of the car.

Tackle each circuit one at a time, and track the voltages through with a voltmeter while they are switched on. As Tatty so kindly says, the schematic elements on http://www.mgb-stuff.org.uk and click on 'Spanners', 'Electrics' and 'Schematics' may help. I hope so, for your fathers sake if nothing else.
Paul Hunt

Check the wiring diagram for the car for each of those items. What you should look for is if they share a common ground. A bad ground connection can take out several leads at one time.

Jim
jmlema

would not worry about the hazzards. If you crank down hard normally it will work correctly. Somehow the switch is prone to getting dirty and only one side works???
Anyway, Paul is dead on with the fuse. You need to take a voltmeter and make sure you have power on both sides. If you elaborate a little after you do a quick check I am sure the problem can be narrowed down for you.
J Arthurs

Check the connections on the back of the hazard switch.
william fox

This thread was discussed between 13/09/2002 and 14/09/2002

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