Tachometer Inaccurate or Inoperative

Tachometer Inaccurate or Inoperative

Diagnostic Fault Information

Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. Diagnostic System Check - Vehicle

Circuit/System Description

The instrument panel cluster (IPC) displays the engine speed based on the information from the powertrain control module (PCM). The PCM converts the data from the engine speed sensor to a 2 pulses/engine revolution signal. The PCM sends the engine speed information via class 2 serial data circuit to the IPC in order to display the engine speed.

Circuit/System Testing

1. Ignition ON, perform the tachometer gage sweep test with the scan tool.

• If the tachometer gage does not sweep from its low to high position, replace the IPC.

Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure. Verification Tests

Refer to Programing and Relearning for IPC replacement, setup, and programming.

Programming and Relearning