Diagnostic Instructions
DTC Descriptor
DTC 036 : Communication Fault
Circuit/System Description
The inflatable restraint Passenger Presence System (PPS) continuously monitors itself for critical faults. If the PPS determines that there is a communication fault or battery voltage has fallen below a threshold causing a communication fault, the PPS
will set DTC 036, turn the passenger air bag status indicator to OFF. Then the PPS will try to communicate with the sensing and diagnostic module (SDM) through a non GMLAN communications circuit that a PPS fault is present. The SDM will then turn the
air bag indicator to ON, and set DTC B0081 indicating a problem within the PPS and will suppress the deployment of the instrument panel (I/P) module.
Conditions for Running the DTC
Ignition voltage is between 9-16 volts.
Conditions for Setting the DTC
| • | The PPS has lost communications with the SDM. |
| • | The PPS receives incorrect messages. |
| • | The SDM has lost or receive no communications with the PPS. |
| • | Battery voltage outside the range of 8-18 volts. |
Action Taken When the DTC Sets
| • | The PPS will set a DTC 036, and then communicate with the SDM via non GMLAN circuit. |
| • | The PPS will also set DTC 056 indicating a PPS internal system fault has occurred until the re-zeroing procedure was performed. |
| • | The SDM will set DTC B0081. |
| • | The SDM disables the I/P module deployment loop. |
| • | The PPS will turn ON the passenger air bag status OFF indicator. |
| • | The SDM commands the AIR BAG indicator ON via GMLAN serial data. |
Conditions for Clearing the DTC
| • | The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used. |
| • | A history DTC will clear once 255 malfunction-free ignition cycles have occurred. |
Diagnostic Aids
This fault indicates that there is either a communication or battery voltage problem.
Reference Information
Schematic Reference
SIR Schematics
Connector End View Reference
SIR Connector End Views
Electrical Information Reference
Circuit/System Testing
- Ignition ON, use the scan tool. Go to the PPS menu, then retrieve the DTCs. Refer to
Passenger Presence System Flash Code Procedures
. Verify DTC 036 is set.
- With the ignition OFF, disconnect the PPS module connector.
- Inspect the component and harness sides of the in-line connector for the PPS. Verify no damage or corrosion exist.
| ⇒ | If the connector for the PPS is damaged, the PPS must be replaced. |
| ⇒ | If the wiring harness side of the PPS connector is damaged, replace the harness side of the connector. |
- Remove the SDM connector and inspect the SDM connector. Verify there is no damage or corrosion found.
Refer to SDM replacement in repair instructions for connector location.
| ⇒ | If the connector for the SDM is damaged, the SDM must be replaced. |
| ⇒ | If the wiring harness side of the SDM connector is damaged, replace the harness side of the connector. |
- Test the PPS communication circuit between the SDM and the PPS for a short to ground, a high resistance, or an open. Verify short to ground, a high resistance, or an open exist.
| ⇒ | Repair the PPS communication circuit. |
- Replace the PPS.
- Use the scan tool to clear all PPS DTCs. Rezero the PPS, refer to
Passenger Presence System Rezeroing
. Verify DTC 036 does not exist.
| ⇒ | If DTC 036 reset replaced the SDM. |
Repair Instructions
Perform the
Diagnostic Repair Verification
after completing the diagnostic procedure.
