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

The instrument panel cluster (IPC) displays the engine speed based on the information from the engine control module (ECM). The ECM converts the data from the engine speed sensor to a 2 pulses/engine revolution signal. The ECM sends the engine speed information via high speed GMLAN serial data circuit to the body control module (BCM). The BCM then sends the information via low speed GMLAN to the IPC to order to display the engine speed.

Schematic Reference

Instrument Cluster Schematics

Connector End View Reference

Instrument Panel, Gages, and Console Connector End Views

Electrical Information Reference

Scan Tool Reference

Scan Tool Data List

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 instrument panel cluster (IPC).

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

Control Module References for IPC replacement, setup, and programming