lost all other power doors lights

1998 LEXUS LS 400
50,000 MILES
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JIM333333
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  • 1 POST
While replacing the battery in my 98 Lexus LS400 I momentarily crossed polarity. I can start the car but have lost all other power: doors, lights and the car will start but all other electrical is lost. The car will only shift by pushing the override button at base of shift lever. Is the PCM relay the problem and which one is it in the fuse panal?
Jan 15, 2012 at 5:18 AM
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CARADIODOC
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  • ASE Certified Mechanic
Look for blown fuses under the hood and inside the car. If you don't find any, you haven't looked far enough. Almost all computers have a diode, (one way valve for electricity), that is installed backward for just this purpose. It conducts like crazy to cause the fuse to blow and protect the computer.
Jan 15, 2012 at 5:24 AM
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KHLOW2008
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  • 41,814 POSTS
  • ASE Certified Mechanic
The main fuses/fusible links are the ones that would blow first. Ensure the ground circuit cables between engine and body are intact. Excessive power surge can fry them as well.
Jan 15, 2012 at 8:00 AM
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