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 00
- Passenger Occupant Classification Sensor
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 Erratic (Wet Seat)
Diagnostic Fault Information
Circuit/System Description
The passenger presence system (PPS) sensor continually monitors itself and if a fault in this circuit occurs, a DTC will set. When the sensing and diagnostic module (SDM) detects this DTC within the PPS, it will notify the customer of the enable/disable status by illuminating 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 disable the deployment of the instrument panel (I/P) module and then illuminate the AIR BAG warning 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 volts or greater than 4.5 volts for 500 milliseconds.
* The PPS detects the voltage at the pressure sensor voltage reference is less than 4.5 volts or greater than 9.1 volts for 500 milliseconds.
* The PPS detects the amperage at the PPS sensor low reference is 25 mA or greater for 500 milliseconds.
Action Taken When the DTC Sets
* The SDM disables the I/P module deployment loop.
* The SDM will illuminate the OFF portion of the PASSENGER AIR BAG ON/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 pressure sensor
* PPS pressure sensor wiring harness connector
1. Verify that DTC B0074 0F is not set.
• If the DTC is set, verify the seat is dry. If the seat is wet, allow 24-48 hours dry time.
2. Ignition OFF, disconnect the harness connector at the PPS sensor.
3. Test for less then 10 ohms between the ground circuit terminal D and ground.
• If greater then the specified range, test the ground circuit for an open/high resistance.
4. Ignition ON, verify a test lamp illuminates between the B+ circuit terminal A and ground.
• If the test lamp does not illuminate, test the B+ circuit for a short to ground or an open/high resistance.
5. Reconnect all PPS components and perform the Passenger Presence System Preload Test (Programming and Relearning) procedure.
6. Clear DTCs, verify DTC B0074 is not set.
• If the DTC sets, replace the PPS sensor.
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