Diagnostic Instructions
| • | Perform the Diagnostic System Check - Vehicle prior to using this diagnostic procedure. |
| • | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
| • | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
DTC Descriptors
DTC B0074 00: Passenger Occupant Classification Sensor CircuitDTC B0074 03: Passenger Occupant Classification Sensor Circuit Voltage Below Threshold
DTC B0074 07: Passenger Occupant Classification Circuit Voltage Above Threshold
DTC B0074 08: Passenger Occupant Classification Sensor Circuit Signal Invalid
DTC B0074 0D: Passenger Occupant Classification Sensor Circuit Resistance Above Threshold
DTC B0074 0E: Passenger Occupant Classification Sensor Circuit Resistance Below Threshold
DTC B0074 0F: Passenger Occupant Classification Sensor Circuit Eratic (Wet Seat)
Diagnostic Fault Information
Circuit | Short to Ground | Low Resistance | High Resistance | Open | Short to Voltage | Performance |
|---|---|---|---|---|---|---|
Pressure Sensor Voltage Reference | B0074 03 | B0074 0E | B0074 0D | B0074 03 | -- | B0074 00, B0074 08, B0074 0F |
Pressure Sensor Low Reference | -- | -- | B0074 0D | B0074 03 | B0074 07 | B0074 00, B0074 08, B0074 0F |
Circuit/System Description
The passenger presence system (PPS) uses a sensor mat located underneath the passenger seat cushion to measure the weight of the occupant sitting in the front passenger seat. The PPS continually monitors itself and if a fault occurs, a DTC will set. When the PPS detects a fault, it will illuminate the OFF indicator on the PASSENGER AIR BAG ON/OFF indicators. Then the PPS will communicate to the SDM through serial data communications that a PPS fault is present. The SDM will then suppress the deployment of the instrument panel (I/P) module and then illuminate the AIR BAG indicator.
Conditions for Running the DTC
Ignition voltage is between 9-16 volts.
Conditions for Setting the DTC
| • | The PPS detects the voltage at the pressure sensor signal is less than 0.5 volt or greater than 4.5 volts for 2 seconds. |
| • | The PPS detects the voltage at the pressure sensor voltage reference is less than 4.5 volts or greater than 9.1 volts for 2 seconds. |
| • | The PPS detects the amperage at the sensor low reference is 25 mA or greater for 2 seconds. |
Action Taken When the DTC Sets
| • | The PPS will set a DTC, and then communicate with the SDM. |
| • | The SDM will request the instrument panel cluster (IPC) to illuminate the passenger air bag status OFF indicator. |
| • | The SDM requests the IPC to illuminate the AIR BAG warning indicator. |
Conditions for Clearing the DTC
| • | The condition for setting the DTC no longer exists. |
| • | A history DTC will clear once 100 malfunction-free ignition cycles have occurred. |
Reference Information
Schematic Reference
Connector End View Reference
Description and Operation
SIR System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References for scan tool information
Circuit/System Testing
- Ignition OFF, Disconnect the PPS module harness connector.
- Ignition OFF, test for less then 1 ohm between the PPS sensor ground circuit terminal 4 and ground.
- Ignition ON, verify a test lamp illuminates between the PPS B + circuit terminal 3 and ground.
- Reconnect all PPS components and perform the Passenger Presence System Rezeroing .
- Verify DTC B0074 does not exist.
Important: When removing connectors, inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector:
• PPS module • PPS module wiring harness connector
| ⇒ | If greater then the specified range, test the circuit for an open/high resistance. |
| ⇒ | If the test lamp does not illuminate, test the circuit for a short to ground or an open/high resistance. if circuit tests normal, replace the PPS. |
| ⇒ | If DTC B0074 is set, replace the PPS. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for PPS replacement, setup, and programming |
