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 Park/Neutral Position (PNP) switch mounts directly onto the transmission housing from the outside, and detects the angular position of the selector shaft. This position is communicated to the Transmission Control Module (TCM) so that certain vehicle control functions can be coordinated with the position of the shift controls. The PNP switch has redundant circuitry to alert the TCM in the event of a single wire or switch failure.

The Neutral signal output of the PNP switch is typically used as confirmation that the transmission is in Neutral before the engine starter is engaged. The PNP switch is interfaced to the starter circuit with weatherproof electrical connectors. The Reverse signal provision may be used to activate vehicle back-up lights and/or Reverse warning devices.

This is a type "A" DTC.