Random/intermittent problems are difficult to diagnose.
Start with main battery connections, make sure they are clean and tight.
Next disconnect electrical connectors and spray with electronics cleaner.
Mechanics have a device which will trace shorts or open wires, but it is labor intensive.
The other possibility is the ignition switch is faulty, like turning the key off.
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Monday, October 4th, 2010 AT 8:49 AM