Tachometer: Testing and Inspection

1. Remove tachometer.
2. Start engine.

Tachometer:

Tachometer Terminal Identification:

3. Using voltage meter, test voltage between Pin 3 and Pin. Refer to Tachometer Terminal Identification table.
4. If battery voltage is OK, go to Step 5. If not OK, check wiring.
5. With the engine running check Pin 1 for a pulse signal. The engine speed produces 3 pulses per revolution. Example: 1,000 rpm is approximately 50 pulses per second. A voltage reading of 3 volts will show that a pulse is being send to the tachometer. If OK, replace tachometer. If not OK, check wire circuit from the PCM.