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 305A: Passenger Occupant Classification Sensor CircuitDTC 305B: Passenger Occupant Classification Sensor Circuit
DTC 305C: Passenger Occupant Classification Sensor Circuit
Diagnostic Fault Information
Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance |
|---|---|---|---|---|
5-Volt Reference | 3003-3059, 300A, 301A, 303A-303E, 305A-305C | 3003-3059, 300A, 301A, 303A-303E, 305A-305C | 3003-3059, 300A, 301A, 303A-303E, 305A-305C | -- |
PPS Sensor Signal | 3003-3059, 300A, 301A, 303A-303E, 305A-305C | 3003-3059, 300A, 301A, 303A-303E, 305A-305C | 3003-3059, 300A, 301A, 303A-303E, 305A-305C | -- |
Low Reference | -- | 3003-3059, 300A, 301A, 303A-303E, 305A-305C | -- | -- |
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 power, ground, and signal circuit. The PPS continually monitors itself and if a fault in this circuit occurs, DTC 305A-305C will set. When the PPS 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 sensing and diagnostic module (SDM) through a serial data communications circuit that a PPS fault is present. The SDM will then set DTC B0081 indicating a problem within the PPS and will suppress 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 PPS sensor signal is less than 0.5 volt or greater than 4.5 volts for 500 milliseconds. |
| • | The PPS detects the voltage at the PPS sensor 5-volt 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 PPS will set a DTC, and then communicate with the SDM. |
| • | The SDM will set DTC B0081. |
| • | The SDM will disable 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 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 harness connector at the inflatable restraint front PPS sensor.
- Ignition OFF, test for less than 1.0 ohm between the low reference circuit terminal C and ground.
- Ignition ON, test for 4.8-5.2 volts between the 5-volt reference circuit terminal A and ground.
- Ignition OFF, disconnect the harness connector at the PPS module.
- Ignition OFF, test for infinite resistance between the signal circuit terminal B and ground.
- Ignition ON, test for less than 1.0 volt between the signal circuit terminal B and ground.
- Test for less than 1.0 ohm between the signal circuit terminal B at the sensor harness connector and terminal 6 at the PPS harness connector.
- If all circuits test normal, test or replace the inflatable restraint PPS 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 module • PPS wiring harness connector
| ⇒ | If not within the specified range, test the low reference circuit for an open/high resistance. If the circuit tests normal, replace the PPS. |
| ⇒ | If less than the specified range, test the 5-volt reference circuit for a short to ground or an open/high resistance. If the circuit tests normal, replace the PPS module. |
| ⇒ | If greater than the specified range, test the 5-volt reference circuit for a short to voltage. If the circuit tests normal, replace the PPS module. |
| ⇒ | If not the specified value, test the signal circuit for a short to ground. |
| ⇒ | If not within the specified range, test the signal circuit for a short to voltage. |
| ⇒ | If greater than the specified range, test the signal circuit for an open/high resistance. |
Repair Instructions
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
| • | Control Module References for PPS replacement, setup, and programming |
