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 03: Passenger Occupant Classification Sensor Circuit Voltage Below ThresholdDTC B0074 07: Passenger Occupant Classification Circuit Voltage Above Threshold
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 | Short to Ground | Low Resistance | High Resistance | Open | Short to Voltage | Performance |
|---|---|---|---|---|---|---|
Pressure Sensor Signal | B0074 03 | B0074 0E | B0074 0D | B0074 03 | B0074 07 | B0074 0F |
Pressure Sensor Voltage Reference | B0074 03 | B0074 0E | B0074 0D | B0074 03 | -- | -- |
Pressure Sensor Low Reference | -- | B0074 0E | B0074 0D | B0074 03 | -- | -- |
Circuit/System Description
The passenger presence system (PPS) uses a silicone filled sensor pad located underneath the passenger seat foam cushion and is connected by a hose clamp to a pressure sensor. The weight of the occupant sitting in the front passenger seat is measured as a pressure change within the bladder by the pressure sensor. The pressure sensor is a 3-wire sensor consisting of a high and low reference, and signal circuit. The PPS monitors the pressure sensor signal circuit and if a fault is detected, DTC will be set. When the PPS detects this DTC it will send out a serial data message and the SDM will notify the customer of the enable/disable status by requesting the instrument panel cluster to illuminate the OFF indicator on the PASSENGER AIR BAG ON/OFF indicators. The SDM will then suppress the deployment of the instrument panel (I/P) module and 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
Important: The PPS pressure sensor is not serviced separately. The PPS replacement with the PPS pressure sensor must be serviced as a complete unit.
- Ignition OFF, disconnect the harness connector at the PPS pressure sensor and inspect the component and harness sides for damage or corrosion.
- Ignition ON, test for 4.5-5.5 volts between the voltage reference circuit terminal A and ground.
- Ignition OFF, remove the AIRBAG Fuse. Test for less than 2.0 ohms between low reference terminal C and ground.
- Ignition OFF, disconnect the harness connector at the PPS module.
- Test for infinite resistance between the signal circuit terminal B and ground.
- Ignition ON, test for less than 1 volt between the signal circuit terminal B and ground.
- Test for less than 1 ohm in the signal circuit between PPS module terminal 6 and belt tension sensor terminal B.
- If all circuits test normal, replace the PPS which includes the pressure sensor.
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 module • PPS pressure sensor wiring harness connector • PPS module wiring harness connector
| ⇒ | If damage or corrosion is found, repair or replace as necessary. |
| ⇒ | If less that the specified range, test the voltage reference circuit for open/high resistance or a short to ground. If the circuit tests normal, replace the PPS. |
| ⇒ | If greater that the specified range, test the voltage reference circuit for a short to voltage. If the circuit tests normal, replace the PPS. |
Important: The AIRBAG Fuse that supplies B+ voltage must be removed to ensure the PPS module is inactive. An active PPS module may cause inaccurate resistance readings.
| ⇒ | If greater than the specified range, test the low reference circuit for open/high resistance. If the circuit tests normal, replace the PPS. |
| ⇒ | If less than the specified value, test the signal circuit for a short to ground. |
| ⇒ | If greater than the specified range, test the signal circuit for a short to voltage. |
| ⇒ | If greater than the specified range, test the signal circuit for open/high resistance. If the circuit tests normal, replace the PPS. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for PPS replacement, setup, and programming |
