MGB: Occational Electrical Issues

Yes, everyone's favorite guessing game...the intermittent electrical problems!

Frankly, I'm being lazy in hopes someone knows the circuitry of the MGA by heart.

Here's the deal: no brake lites, turn signals nor fuel gauge--then after a few miles, everything is working again. Loose wire, eh?? Which one? I've looked and all seems ok. The car is a '59 TwinCam

Thanks!

Paul

Paul, I don't have my MGA schematic here at work, but from my electronics experience it sounds like a problem with losing the +12v from these circuits at the same time. Two potential sources for this, one is the screw terminal on the fuse block and the other would be a multiple male / female bullet connector between the chassis and dash wiring harness. The female connectors are known to crack internally and loose tension on the male bullets causing intermittant connections. I'd get a couple of new female connectors and start replacing these and testing. If it doesn't fix the problem move on to another connector, or if you want just replace them all. It's not terribly expensive, the double female connectors go for .95 each from Moss.

It is most likely either the fuse not making good connection or else the green wires connected to the fuse block making a bad connection.

There are 4 green wires connected to the fuse block. One goes to the brake light switch, one to the turn signal flasher, one to the wiper motor and one to the fuel gauge. The green wire to the fuel gauge also powers the heater fan and with the 1500 style tail lights it also powers the turn signal switch.

It could also be the fuse itself. I have seen fuses go intermittent with age. Make sure you are using the correct fuses. British fuses are rated differently than American fuses and if you replace them with American fuses you could fry your wiring.

Green wires & bullet connectors. Thats what I was looking for. Thanks Bill & Jeff. I'll give those a look.

Paul

Paul'
How did you make out? It has to be a loose connection somewhere.

Peter

I've not been to the garage all week, guys so I'm not able to report any results. I hope to clean up from the tropical storm that blew thru here yesterday, and then wind up the A for a look-see and spin. Will report back with results.

Paul

T'was the top bundle of green wires onto the fusebox. Looks like its fixed for now. Thanks, Paul