Car Fuses and Wiring
Ford Ranger XL
Late Model 1979-New Ford Mustangs

Why does a fuse blow everytime the headlights are turned on while playing the stereo in a 1990 Ford Mustang LX?


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2005-04-22 23:38:29
2005-04-22 23:38:29

You have grounded to the radio light wire, not the ground. It is a negative wire that is in the harness, and when you turn on headlights you blow the dash lights. Remove your radio ground from the car, and find a new ground. It should be a large black and green wire (larger than all the others). replace the fuse, and turn on the will see your old ground wire is actually hot now. Common mistake, and it tests like ground wire with lights OFF, but not on. Relentless


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