Circuit Description
WARNING: This page is about a different car, the 2003 Oldsmobile Bravada, 2003 GMC Envoy XL, 2003 GMC Envoy, and 2003 Chevrolet TrailBlazer. However, it is still accessible from the selected car via links, so may be relevant.
The IPC monitors the engine speed signal to determine the tachometer position. If the IPC determines the engine speed signal voltage is out of the normal operating range, a DTC will set.