Diagnostic Instructions
DTC Descriptors
DTC B0074 03: Passenger Occupant Classification Sensor Circuit Voltage Below Threshold
DTC B0074 07: Passenger Occupant Classification Sensor Circuit Voltage Above Threshold
DTC B0074 08: Passenger Occupant Classification Sensor Circuit Signal Invalid
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
Connector End View Reference
Component Connector End Views
Description and Operation
SIR System Description and Operation
Electrical Information Reference
Scan Tool Reference
Control Module References 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 wiring harness connector |
- Ignition OFF, disconnect the harness connector at the PPS module.
- Ignition OFF, test for less than 1 ohm between the ground circuit terminal D and ground.
| ⇒ | If greater then the specified range, test the ground circuit for an open/high resistance. |
- 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. |
- Reconnect all PPS components and perform the Passenger Presence System Rezeroing. Verify DTC B0074 is not set as current.
| ⇒ | If DTC B0074 is set, replace the PPS. |
Repair Instructions
Perform the
Diagnostic Repair Verification after completing the diagnostic procedure.
