Instrument Panel Cluster (IPC) Description and Operation: Speedometer

WARNING: This page is about a different car, the 2002 Oldsmobile Intrigue. However, it is still accessible from the selected car via links, so may be relevant.

The IPC displays the vehicle speed based on the information from the PCM. The IPC receives a class 2 message from the PCM indicating the vehicle speed. The speedometer defaults to 0 kph (0 mph) if:

The PCM detects a malfunction in the vehicle speed sensor circuit.
The IPC detects a loss of class 2 communications with the PCM.