Circuit Description

WARNING: This page is about a different car, the 2004 Chevrolet Corvette. However, it is still accessible from the selected car via links, so may be relevant.

IMPORTANT: The driver door lock cylinder is connected to the driver door key switch and driver door latch using mechanical linkages. When the driver door lock cylinder is rotated to the UNLOCK position, the driver door is unlocked mechanically. The passenger door lock cylinder is connected to the passenger door key switch and passenger door latch using mechanical linkages. When the passenger door lock cylinder is rotated to the UNLOCK position, the passenger door is unlocked mechanically.

The driver or passenger door key switch signal circuits provide input to the driver door module (DDM) or passenger door module (PDM) when the driver or passenger door lock cylinder is rotated to the UNLOCK position. This input allows the door module to detect a door UNLOCK request. The door module provides power and ground to the door key switch. When the door lock cylinder is rotated to the UNLOCK position, a ground is supplied through the door key switch to the signal circuit, which is pulled low. When the DDM detects low voltage on the driver door key switch signal circuit, it sends a message on the serial data line to the PDM to UNLOCK the passenger door. When the PDM detects low voltage on the passenger door key switch signal circuit, it sends a message on the serial data line to the DDM to UNLOCK the driver door. The messages sent on the serial data line are also used by other systems to execute certain functions. The DDM and PDM monitor the signal circuits to determine how long the ground has been applied. If the DDM or PDM detects that the ground is applied for greater than 20 seconds, a DTC is set.