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MG MGB Technical - HELP!!!!!!

Hey there. I have a '79 B and it's been nothing but a pain in the ass. It was out of commission for the past 7 months and I've just gotten it running again. Replaced the battery for the third time in 2 years. Replaced the spark plugs. Adjusted the timing. Cleaned out the carb. Now the break lamps, blinkers, hazards and wipers are non-functioning. They worked about 3 months ago...but now they're dead. The wipers will work in the process of turning the car over but once the engine kicks on, they cease to function. Any suggestions....E-MAIL ME PLEASE!!!

stepladder@hotmail.com or even call at (972)727-1999

Thanks

Joe
Joe

Although bad connections to the green circuit
and purple circuit are possible (check the fuse
box connections for starters), these problems
are often bad grounds. There is a common
ground connection (bunch of black wires) on the
right hand side of the engine compartment. The
screw securing these could be loose/corroded.

Also check the connector to the alternator itself.
If this is loose, you will have low voltage.
Also ground strap from the transmission to the
transmission crossmember.
Ronald

Joe,
I would start checking all the grounds. If that does not work. Get a wiring diagram and start checking the brown wire then the white then the purple ect. Until you find where the problem is. This site has a great wiring section in it. Use it.

Steve
Steve

Nope...that ain't it. But thanks. THe ground cluster is in the middle of my trunk. The alternator was tight. I'm pulling my hair out here.
Joe

Thanks, Steve
Joe

could you tell me where the wiring diagram is on this site? thanks
Joe

http://www.mgbexperience.com/view/?service/wiring-later.jpg
gerry masterman

http://www.mgbexperience.com/electrical/
Here's another great site for help. Electrical problems are hard tp trace down. You need to take one circiut at a time and check everything out then move on the the next. You have grounds in several places. Luclar connectors are known for bad connections, too.
gerry masterman

Joe,

Another thought about grounding. Each of the lamp fixtures needs to be grounded to the body for your turn signals to work properly. Check to see if each securing screw is tight and making good contact. If not the current will backfeed through the system looking for ground, and strange things can happen.

Regards,

L.C. '74 B/GT
Larry C.

The brake lights, turn signals and wipers are on the green fuse (2nd fuse up in the 4-way fuse-block) but so are the instruments, heater fan, washers, reverse lights etc. If any of these work it is not the fuse but one of the several bullet and multi-plug connectors in the green circuit.

Whilst things on the dash and wipers tend to have a common ground the rear light clusters get their ground from the body fixings. Check the brake light switch on the pedal box for 12v on both terminals when the pedal is pushed. The RB turn signals share a different ground with all the other front lights. The trunk ground feeds other things like fuel pump and the ancillary rear lights.

The hazards run off the brown (always hot) via an in-line fuse. Check this fuse as well as the switch. A bad hazard switch can also stop the turn signals from even lighting up, let alone flashing.

If the wipers work while cranking but not when the engine is running it sounds like they are wired incorrectly.

Just tackle one fault at a time and don't expect a 'magic bullet'.

You will find diagrams broken down into individual circuits on the above web site - select 'Spanners', 'Electrics' and 'Schematics'.
Paul Hunt

My money is on a bad ignition switch - the fact that things work on cranking but not when you release the key is the clue.
Chris Betson

But then the engine wouldn't run ...
Paul Hunt

This thread was discussed between 21/12/2001 and 23/12/2001

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