B0074
DTC B0074
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle (Initial Inspection and Diagnostic Overview) prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis (Initial Inspection and Diagnostic Overview) for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions (Initial Inspection and Diagnostic Overview) provides an overview of each diagnostic category.
DTC Descriptors
DTC B0074 01
- Passenger Occupant Classification Sensor Circuit Short to Battery
DTC B0074 02
- Passenger Occupant Classification Sensor Circuit Short to Ground
DTC B0074 08
- Passenger Occupant Classification Sensor Circuit Signal Invalid
DTC B0074 11
- Passenger Occupant Classification Sensor Circuit Above Maximum Threshold
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 a failure within itself.
Action Taken When the DTC Sets
* The PPS will set a DTC, and then communicate with the SDM.
* The SDM disables the I/P module deployment loop.
* The PPS will illuminate the passenger air bag status OFF indicator.
* The SDM requests the instrument panel cluster (IPC) to illuminate the AIR BAG 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
SIR Schematics ([1][2]Air Bag Systems)
Connector End View Reference
Component Connector End Views (Connector Views)
Description and Operation
SIR System Description and Operation (Description and Operation)
Electrical Information Reference
* Circuit Testing (Component Tests and General Diagnostics)
* Connector Repairs (Component Tests and General Diagnostics)
* Testing for Intermittent Conditions and Poor Connections (Component Tests and General Diagnostics)
* Wiring Repairs (Component Tests and General Diagnostics)
Scan Tool Reference
Control Module References (Programming and Relearning) for scan tool information
Circuit/System Testing
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
1. Ignition OFF, Disconnect the PPS module harness connector.
2. Ignition OFF, test for less then 1 ohm between the PPS sensor ground circuit and ground.
• If greater then the specified range, test the circuit for an open/high resistance.
3. Ignition ON, verify a test lamp illuminates between the PPS B + circuit terminal A and ground.
• 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.
4. Reconnect all PPS components and perform the Passenger Presence System Rezeroing (Programming and Relearning).
5. Verify DTC B0074 does not exist.
• If DTC B0074 is set, replace the PPS.
Repair Instructions
Perform the Diagnostic Repair Verification (Verification Tests) after completing the diagnostic procedure.
* SIR/SRS Wiring Repairs (Component Tests and General Diagnostics)
* Control Module References (Programming and Relearning) for PPS replacement, setup, and programming