Operation CHARM: Car repair manuals for everyone.

Filament Check




1. Attach probe circuit tester (in volt range) to middle portion of each filament.



^ When measuring voltage, wrap tin toil around the top of the negative probe. Then press the foil against the wire with your finger.



2. If a filament is burned out, circuit tester registers 0 or 12 volts.



3. To locate burned out point, move probe to left and right along filament. Test needle will swing abruptly when probe passes the point.