B0077

Diagnostic Chart 1 Of 2:

Diagnostic Chart 2 Of 3:

Diagnostic Chart 3 Of 3:

Schematics:

CIRCUIT DESCRIPTION
When you first turn ON the ignition, the inflatable restraint Sensing and Diagnostic Module (SDM) performs tests to diagnose critical malfunctions within itself. The SDM provides input power to the inflatable restraint Side Impact Sensor (SIS). When input power is first detected, the SIS responds by performing internal diagnostics. Next the SIS sends an ID message to the SDM. The SDM will consider this to be a valid ID if the response time is less than 5 seconds after the SIS is powered up.The SIS will continually communicate a status message to the SDM. The SDM can reset the SIS by removing and applying power to it.

CONDITIONS FOR RUNNING THE DTC
^ Ignition 1 voltage is within the normal operating voltage range.
^ The SDM monitors the inflatable restraint side impact sensor loop with the ignition ON.

CONDITIONS FOR SETTING THE DTC
The SDM has detected one of the following conditions due to a fault in the SIS interface circuit:
^ A valid ID message is not received within 5 seconds of the SIS being powered up.
^ Status message is not received.
^ The SDM has failed twice to reset the SIS.

ACTION TAKEN WHEN THE DTC SETS
^ The SDM commands ON the AIR BAG warning lamp via Class 2 serial data.
^ The SDM attempts to reset the SIS.

CONDITIONS FOR CLEARING THE DTC
^ Current DTC
- The SDM has detected correct operation.
- The SIS sends an OK message to the SDM.
^ History DTC
- You issue a scan tool CLEAR CODES command.
- Once 255 malfunctions free ignition cycles have occurred.

DIAGNOSTIC AIDS
An inflatable restraint side impact sensor (SIS) circuit open, high resistance, low resistance, short to ground, or short to voltage can cause an intermittent condition. Inspect the inflatable restraint side impact sensor high and sensor low circuits carefully for cutting and/or chafing.

TEST DESCRIPTION
The numbers below refer to the step numbers on the diagnostic table:
2. This step checks the inflatable restraint side impact sensor wiring harness connector for corrosion or damaged terminals.
4. This step checks the inflatable restraint side impact sensor for corrosion or damaged terminals.
7. This step checks the SDM wiring harness connector for corrosion or damaged terminals.
12. This step checks to see if there is an open or a high resistance in the inflatable restraint side impact sensor low circuit.
14. This step checks to see if there is an open or a high resistance in inflatable restraint side impact sensor high circuit.
16. This step checks to see if there is a short between the inflatable restraint side impact sensor low circuit and the inflatable restraint side impact sensor high circuit.
18. This step checks to see if there is a short to ground in the inflatable restraint side impact sensor high circuit.
20. This step checks to see if there is a short to ground in the inflatable restraint side impact sensor low circuit.
22. This step checks to see if there is a short to voltage in the inflatable restraint side impact sensor high circuit.
24. This step checks to see if there is a short to voltage in the inflatable restraint side impact sensor low circuit.
27. This step determines if the problem was solved by replacing the inflatable restraint side impact sensor (SIS) or if there is a malfunctioning SDM.