• | Perform the Diagnostic System Check - Vehicle prior to using the diagnostic procedure. |
• | Review Strategy Based Diagnosis for an overview of the diagnostic approach. |
• | Diagnostic Procedure Instructions provides an overview of each diagnostic category. |
Circuit | Short to Ground | High Resistance | Open | Short to Voltage |
---|---|---|---|---|
Pressure Sensor Low Reference | -- | B0074 03 | B0074 03 | -- |
Pressure Sensor Signal | B0074 07 | B0074 03, 07 | B0074 03, 07 | B0074 03 |
Pressure Sensor Voltage Reference | B0074 07 | B0074 07 | B0074 07 | B0074 03 |
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, 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 suppress the deployment of the instrument panel (I/P) module and then illuminate the AIR BAG indicator.
Ignition voltage is between 9-16 volts.
• | 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. |
• | 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. |
• | The condition for setting the DTC no longer exists. |
• | A history DTC will clear once 100 malfunction-free ignition cycles have occurred. |
Control Module References for scan tool information
Important:
• The PPS pressure sensor is not serviced separately. The PPS replacement with the PPS pressure sensor must be serviced as a complete unit. • 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 AIR BAG BATT 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. |
Perform the Diagnostic Repair Verification after completing the diagnostic procedure.
• | Control Module References for PPS replacement, setup, and programming |