For 1990-2009 cars

### 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 Descriptor

DTC 024: PPS Ignition 1 Voltage Performance

### Diagnostic Fault Information

Circuit | Short to Ground | Open/High Resistance | Short to Voltage | Signal Performance
--- | --- | --- | --- | ---
Ignition Voltage | 024 | 024 | -- | --

### Circuit/System Description

The passenger presence system (PPS) module has an ignition 1 voltage input. The PPS continually monitors itself for faults. If the voltage on this circuit falls below a certain threshold, the PPS will set DTC 024. 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 serial data communication 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 ignition 1 voltage is less than 8 volts 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 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 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.

### Diagnostic Aids

The PPS will set DTC 024 as a history code only, when the ignition voltage has fallen below 8 volts. This is a normal condition for DTC 024 and it should be diagnosed as a current DTC.

### 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

• | Circuit Testing

• | Connector Repairs

• | Testing for Intermittent Conditions and Poor Connections

• | Wiring Repairs

### 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 wiring harness connector

1. Ignition OFF, disconnect the harness connector at the PPS module.
2. Ignition OFF, test for less than 1.0 ohm between the ground circuit terminal 5 and ground.

⇒ | If greater than the specified range, test the low reference circuit for an open/high resistance.

3. Ignition ON, verify that a test lamp illuminates between the ignition voltage circuit terminal 9 and ground.

⇒ | If the test lamp does not illuminate, test the ignition voltage circuit for a short to ground or an open/high resistance.

4. If all circuits test normal, test or replace the PPS module.

### Repair Instructions

Perform the Diagnostic Repair Verification after completing the diagnostic procedure.

• | SIR/SRS Wiring Repairs

• | Control Module References for PPS replacement, setup, and programming