When the ignition is turned ON, the inflatable restraint sensing and diagnostic module (SDM) enters the power-up mode and performs self tests of critical internal functions. After completing the power-up mode, the SDM establishes communication with the Passenger Presence System (PPS) module. The PPS module responds by performing diagnostic tests for proper circuit continuity and shorts to ground and voltage within the PPS. If the PPS module detects a malfunction, a DTC will set and the module communicates to the SDM that a malfunction has occurred, while turning the passenger air bag status indicator to OFF. The SDM responds by disabling the instrument panel (I/P) module deployment loop, setting DTC B0081 and commanding the AIR BAG indicator ON. The SDM notifies the driver of a PPS or SIR malfunction by turning ON the AIR BAG indicator. The DTCs that the PPS sets are non GMLAN and have to be flashed through the PASSENGER AIR BAG ON/OFF indicators. 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 passenger presence system (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 the flashing procedure is 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.

Without PPS DTCs Present

1. Ignition ON, with the scan tool, request the PPS to check for DTCs.
2. First observe the PASSENGER AIR BAG ON and OFF indicators illuminating together and individually for several seconds.
3. Next observe both the PASSENGER AIR BAG ON and OFF indicators illuminated simultaneously for 1-2 seconds just before the scan tool asks if both indicators are illuminated.

⇒	If both the PASSENGER AIR BAG ON and OFF indicators did illuminate simultaneously at the end request sequence, no PPS DTCs are present.

⇒	If either of the passenger air bag indicators was always OFF, the indicator may be faulty. Refer to Passenger Presence System Indicator Circuit Malfunction.

With PPS DTCs Present

1. Ignition ON, with the scan tool, request the PPS to check for DTCs.
2. Observe the PASSENGER AIR BAG ON and OFF indicators illuminating together and individually for several seconds.
3. Observe the PASSENGER AIR BAG ON and OFF indicators turned OFF for 1 second.
4. Observe the illumination of the PASSENGER AIR BAG OFF indicator. Count the number of times the OFF indicator flashes to obtain the first number of the DTC. This will be an Odd number.
5. Observe the illumination of the PASSENGER AIR BAG ON indicator. Count the number of times the ON indicator flashes to obtain the second number of the DTC. This will be an Even number.
6. To determine if a code is current or history, the PPS will flash current DTCs 2 times consecutively and flash history DTCs once.

⇒	If a DTC is found, refer to the Diagnostic Trouble Code (DTC) List - Vehicle.

⇒	If either of the passenger air bag indicators was always OFF, test the inflatable restraint instrument panel module indicator. Refer to Passenger Presence System Indicator Circuit Malfunction.