Tachometer Out Of Order

OUTPUT SIGNAL TO MAIN DISPLAY INSTRUMENT PANEL





Symptom Of Fault.
Tachometer does not work.





Diagnostic Procedure.
1. Check The Wiring.

- Check The Wiring between pin 58 of the Trionic control module and pin 6 of the main instrument display panel for continuity.
- Check the lead for open circuit and shorting.

Is the lead OK?

YES: Continue with point 2.
NO: Rectify the fault.

2. Check the output signal

- Plug in the Trionic control module.
- Unplug the main instrument display panel's connector.
- Start the engine and run it at idling speed.
- Take a frequency reading across pin 6 of the connector and a good ground.
At idling speed, about 900 rpm, the frequency should be about 30 Hz.

Is the reading OK?

YES: Continue fault diagnosis in the Electrical System, Main Instrument Display Panel.
NO: Continue at "Before Replacing a Control Module". Component Tests and General Diagnostics