B0074
DTC B0074
Diagnostic Instructions
* Perform the Diagnostic System Check - Vehicle Diagnostic System Check - Vehicle prior to using this diagnostic procedure.
* Review Strategy Based Diagnosis Strategy Based Diagnosis for an overview of the diagnostic approach.
* Diagnostic Procedure Instructions Diagnostic Procedure Instructions provides an overview of each diagnostic category.
DTC Descriptors
DTC B0074 01
-
Passenger Presence Sensor Circuit Short to Battery
DTC B0074 02
-
Passenger Presence Sensor Circuit Short to Ground
DTC B0074 08
-
Passenger Presence Sensor Circuit Signal Invalid
DTC B0074 11
-
Passenger Presence Sensor Circuit Above Maximum Threshold
Diagnostic Fault Information
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 presence sensor. The weight of the occupant sitting in the front passenger seat is measured as a pressure change within the bladder by the presence sensor. The presence 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 inflatable restraint 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 passenger instrument panel air bag and then illuminate the SIR system AIR BAG indicator.
Conditions for Running the DTC
Ignition voltage is between 9-16 V.
Conditions for Setting the DTC
* The PPS detects the voltage at the PPS sensor is less than 0.5 V or greater than 4.5 V 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 disables the passenger instrument panel air bag deployment loop.
* The PPS illuminates the passenger air bag status OFF indicator.
* The SDM requests the instrument panel cluster (IPC) to illuminate the SIR system AIR BAG warning lamp.
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
If either the SDM or PPS were replaced verify that the correct part numbers were used for the vehicle application.
Reference Information
Schematic Reference
SIR Schematics [1][2]Air Bag Systems
Connector End View Reference
Component Connector End Views 1-2 Shift Solenoid (SS) Valve (MN5)
Description and Operation
SIR System Description and Operation Description and Operation
Electrical Information Reference
* Circuit Testing Circuit Testing
* Connector Repairs Connector Repairs
* Testing for Intermittent Conditions and Poor Connections Testing for Intermittent Conditions and Poor Connections
* Wiring Repairs Wiring Repairs
* SIR/SRS Wiring Repairs SIR/SRS Wiring Repairs
Scan Tool Reference
Control Module References Programming and Relearning for scan tool information
Circuit/System Testing
Note:
When removing connectors, inspect for damage or corrosion. Damage or corrosion in the following requires repair or replacement of the affected component/connector:
* PPS sensor
* PPS sensor wiring harness connector
1. Ignition OFF, disconnect the harness connector at the PPS sensor.
2. Ignition OFF, test for less than 5 ohms between the PPS sensor ground circuit terminal D and ground.
• If greater than the specified range, test the ground circuit for an open/high resistance.
3. Ignition ON, verify a test lamp illuminates between the PPS 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.
4. Reconnect all PPS components and perform the Passenger Presence System Programming and Setup Programming and Relearning.
5. Verify DTC B0074 is not set.
• If DTC B0074 is set, replace the PPS sensor.
Repair Instructions
Perform the Diagnostic Repair Verification Verification Tests after completing the diagnostic procedure.
Control Module References Programming and Relearning for PPS replacement, programming and setup