DTC 056

DTC 056

CIRCUIT DESCRIPTION
The inflatable restraint passenger presence system (PPS) continuously monitors for critical faults. If the PPS determines there is a fault internal to the electronic control unit (ECU) or sensor mat, the PPS will set DTC 056, turn the passenger air bag status indicator to OFF, and notify the sensing and diagnostic module (SDM) of a fault in the PPS through a non class 2 communications circuit. Other DTCs like DTC 034 or DTC 036 may set along with DTC 056. Diagnose all current DTCs before diagnosing DTC 056. The PPS, heated seat element, and seat bottom cushion is only service as a complete kit, which is a calibrated system and must be replaced as a complete unit. If a service kit was installed, DTC 056 will be set current and the Rezeroing Procedure must be performed before the DTC can be cleared.

DTC DESCRIPTOR
This diagnostic procedure supports the following DTC:
DTC 056 PPS Internal System Fault

CONDITIONS FOR RUNNING THE DTC
Ignition 1 voltage is within the normal operating voltage range.

CONDITIONS FOR SETTING THE DTC
- PPS ECU internal electronic fault
- PPS Sensor mat internal electronic fault
- PPS Service kit was installed

ACTION TAKEN WHEN THE DTC SETS
- The PPS will set a DTC 056, then communicate with the SDM via non class 2 circuit.
- The SDM will set DTC B0092.
- The SDM disables the instrument panel module (IPM) deployment loop.
- The PPS will turn ON the passenger air bag status OFF indicator.
- The SDM commands the AIR BAG indicator ON via class 2 serial data.

CONDITIONS FOR CLEARING THE DTC
- The condition responsible for setting the DTC no longer exists.
- You issue a scan tool CLEAR DTCs command.
- A history DTC will clear once 255 malfunction free ignition cycles have occurred.
- If service kit was installed, you performed the rezeroing procedure with a scan tool.

DIAGNOSTIC AIDS
DTC 034 or DTC 036 may set along with DTC 056. Diagnose all current DTCs before diagnosing DTC 056. This DTC 056 indicates that you have installed a service kit or have an internal fault to the ECU or sensor mat.

TEST DESCRIPTION

Steps 1-7:

The number below refer to the step numbers on the diagnostic table.
2. This step is requesting the PPS DTCs, checking to see if DTC 034 or DTC 036 is current.