When the ignition is turned ON, the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. When the SDM has completed the power-up mode the SDM will establish communication with the passenger presence system (PPS). The PPS will respond by performing diagnostic tests to check for proper circuit continuity and for shorts to ground and voltage within the PPS. If the PPS detects a malfunction, the PPS will set a DTC, then communicate through a non class 2 or GMLAN communications circuit to the SDM that a malfunction has occurred, while turning the passenger air bag status indicator to OFF. The SDM will respond by disabling the instrument panel (I/P) module deployment loop, setting DTC B0092 or B0098 and commanding the AIR BAG indicator ON. The SDM notify the driver of a PPS or SIR malfunction by turning ON the AIR BAG indicator on the cluster. The DTCs that the PPS set are non class 2 or GMLAN and have to be flashed through the PASSENGER AIR BAG ON/OFF indicators located in the rearview mirror. The procedures below are designed to assist in the flashing of these codes. Before you start, read these procedures carefully and completely. For further information regarding the PPS refer to SIR System Description and Operation .

Important: When flashing PPS codes, the instrument panel cluster (IPC) and dash lights will begin dimming on and off. This is normal operation during the flashing procedure and does not indicate additional system faults.

Important: If after 30 seconds of a successful request to flash codes and no additional flashes are observed, then the PPS does not have any stored codes.

1. Empty the front outboard passenger seat.
2. Install a scan tool.
3. Turn ON the ignition, with the engine OFF.
4. With a scan tool, request the PPS to flash DTCs.
5. When the PPS receives a valid request to flash DTCs, the PPS will perform the following:

5.1.	Illuminate both PASSENGER AIR BAG ON and OFF indicators for 1 second.

5.2.	Turn OFF both PASSENGER AIR BAG ON and OFF indicators for 1 second.

5.3.	Flash the first number of the DTC using the OFF indicator. Count the number of times the OFF indicator flashes to obtain the first number of the DTC.

5.4.	Flash the second number of the DTC using the ON indicator. Count the number of times the ON indicator flashes to obtain the second number of the DTC.

5.5.	When the flashing procedure is initiated, to determine if a code is current or history, the PPS will flash current DTCs two times consecutively and flash history DTCs once.

6. If the flashing procedure was unsuccessful repeat this procedure. Due to the communication status between the SDM and the PPS module, this procedure may have to be repeated until a successful flashing attempt has been achieved.
7. Refer to the Diagnostic Trouble Code (DTC) List - Vehicle , to diagnose the DTCs you have obtained.