Symptom Related Diagnostic Procedures

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

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 to determine point where tester needle swings abruptly.

^ When measuring voltage, wind a piece of tin foil around the top of the negative probe and press the foil against the wire with your finger.