1992 Ford F-150 Dead Short

DANIEL79

MEMBER
1992 FORD F-150
6 CYL
2WD
AUTOMATIC
132,127 MILES

The truck has a short. If I leave the cables hooked up to the battery it will drain the battery. We hooked a tester light to the battery despite the key being turned off the light would remain on. The light went off when we took off the ignition switch at the bottom of the steering wheel. We replaced the switch with a new one but after replacing the switch the light came back on. After more searching the came back off after removing a wire from the cylinoid starter switch mounted on the fender the light went off again. I would like to know if there any common shorts in a 1992 Ford F150 straight six.

1 Reply

MERLIN2021

MECHANIC
17,250 POSTS

Get an analog voltmeter remove the negative battery cable, attach the Black lead to the battery post, Red lead to cable end, then pull fuses one at a time, make sure there are no accessories or lights in the on position, Key off! Close the door after each fuse and check meter, when you pull the fuse for the bad curcuit, the meter will drop to 1 volt or so. Check all fuses, even under the hood. If meter does not drop, remove the battery connection from the alternator, if it drops now, the diodes are bad in the alternator. Put the fuse back in were it goes as you go so you don't forget which fuse goes were!
https://www.2carpros.com/first_things/why_is_my_car_battery_dead_over_night.htm