1988 Ford Mustang

1988 FORD MUSTANG
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SOMO777
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Electrical problem
1988 Ford Mustang V8 Two Wheel Drive Manual

Put the battery in backwards and screwed everything up. Got new battery, starter, and alternator. It won't hold a charge. It runs, then the battery gets drained and won't start. Can you help me. I am very frustrated and tried everything, and mechanic couldn't fix it. He didn't know.
Jul 29, 2010 at 7:53 PM
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MHPAUTOS
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HI there,

you need to do a current draw test, this will help locate where the drain is, if you mechanic does not know how to do this simple test, re post and i will advise further.

mark (mhpautos)
Jul 30, 2010 at 4:20 AM
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SOMO777
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Thank you very much, how do you do a draw test and then do you give it to the mechanic. My mechanic did not know how to do.
Jul 30, 2010 at 10:47 AM
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MHPAUTOS
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This is a test the mechanic will have to do, what you do is place an Amp meter between Battery Pos (+) and the battery cable, do not try and start engine....... with the ignition key out and doors closed, read the current draw on the amp meter, you will be looking for .25 Amps thereabouts, if above this, say .3 or higher, you can then pull fuses one at a time if the amps drop you have located the faulty circuit that is drawing to much current, unplug the alternator as well as a test as a faulty diode will back feed current and still give a charge rate, check for any fusible links as well an disconnect these also.

mark (mhpautos)
Jul 30, 2010 at 5:35 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.