Circuit Description
WARNING: This page is about a different car, the 2003 GMC Sierra, 2003 GMC Cab & Chassis Sierra, 2003 Chevrolet Silverado, and 2003 Chevrolet Cab & Chassis Silverado. 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.