GM Service Manual Online
For 1990-2009 cars only

Circuit Description

The inflatable restraint passenger presence system (PPS) is used to monitor the weight of an occupant on the front outboard passenger seat and communicate the status to the sensing and diagnostic module (SDM) whether to enable or suppress the deployment of the instrument panel (I/P) module. The PPS consist of an electronic control module, silicone filled sensor pad, pressure sensor, seat belt tension retractor sensor, wiring harness, and PASSENGER AIR BAG ON/OFF indicators. The silicone filled sensor pad is located under the passenger seat foam cushion and is connected by a hose clamped to the 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 sends a voltage signal to the PPS module. If the pressure from the occupants weight is less than a specified value, the PPS module will send a suppress signal to the SDM to disable the I/P module. If the pressure from the occupants weight is higher than a specified value, the PPS module will send an enable signal to the SDM to enable the I/P module. The PPS module will notify the customer of the enable/disable status by turning on one of the PASSENGER AIR BAG ON/OFF indicators located on the instrument panel. The PPS monitors itself for faults and will set flash DTCs if a fault is detected. The PPS will also notify the SDM of a fault. The SDM will respond by setting either DTC B0092 or B0098 and requesting the instrument panel cluster (IPC) to turn the AIR BAG indicator ON.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC 064 PPS Communication/ID Performance

Conditions for Running the DTC

Ignition 1 voltage is within the normal operating voltage range.

Conditions for Setting the DTC

    • The PPS has lost communications with the SDM.
    • The PPS verification ID does not match the ID that is stored in the SDM.

Action Taken When the DTC Sets

    • The SDM disables the I/P module deployment loop.
    • The SDM commands the AIR BAG indicator ON via class 2 serial data.

Conditions for Clearing the DTC

    • The condition responsible for setting the DTC no longer exists.
    • You issue a scan tool CLEAR DTCs command.
    • A history DTC will clear once 255 malfunction free ignition cycles have occurred.

Diagnostic Aids

Important: DTC B0098 is an indication that the SDM has received an incorrect PPS verification ID. The SDM will continue to request the verification ID from the PPS for 5 seconds. If the SDM does not receive the correct verification ID from the PPS within 5 seconds, the SDM will set DTC B0098 as current, illuminate the AIR BAG indicator, and disable the I/P module deployment loop. If either the SDM or PPS were replaced make sure the correct part numbers were used for the vehicle application.

DTC B0092 or B0098 will set if the PPS has a current malfunction and has set DTC 064. The SDM will set DTC B0092 or B0098 as current and command the AIR BAG indictor ON. This is done to notify the driver of any PPS malfunctions. When DTC B0092 or B0098 are present it is important to check the PPS for any current DTCs. Refer to Passenger Presence System Flash Code Procedures .

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This step tests for current PPS DTCs.

  2. This step tests for a short to ground, a high resistance, or an open in the PPS class 2 serial data circuit.

  3. This step tests for a short to voltage in the PPS class 2 serial data circuit.

Step

Action

Yes

No

Schematic Reference: SIR Schematics

Connector End View Reference: SIR Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, request the passenger presence system (PPS) to flash DTCs. Refer to Passenger Presence System Flash Code Procedures .

Does the PPS indicate that DTC 064 is current?

Go to Step 3

Go to Step 13

3

Does the scan tool indicate that DTC B0098 is current?

Go to DTC B0098

Go to Step 4

4

  1. Turn OFF the ignition.
  2. Disconnect the PPS module connector. Refer to Inflatable Restraint Passenger Presence System Replacement - Front .
  3. Inspect the PPS module terminals and harness connector for damage or corrosion.

Does the PPS module terminals or harness connector exhibit any signs of damage or corrosion?

Go to Step 5

Go to Step 6

5

  1. If the PPS module terminals are damaged, replace the PPS. Refer to Inflatable Restraint Passenger Presence System Replacement - Front .
  2. If the PPS harness connector is damaged, replace the connector. Refer to Connector Repairs.

Did you complete the replacement?

Go to Step 13

--

6

  1. Disconnect the main seat harness connector located under the RF seat. Refer to Power Seat Connector End Views.
  2. Inspect both halves of the connector for corrosion or damage. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs.

Did you find and correct the condition?

Go to Step 13

Go to Step 7

7

  1. Disconnect the sensing and diagnostic module (SDM) connector. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .
  2. Inspect the SDM connector for corrosion or damage. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs.

Did you find and correct the condition?

Go to Step 13

Go to Step 8

8

Test the PPS class 2 serial data circuit for the following:

    • A short to ground
    • A high resistance
    • An open

Refer to Circuit Testing and Wiring Repairs.

Did you find and correct the condition?

Go to Step 13

Go to Step 9

9

  1. Turn ON the ignition, with the engine OFF.
  2. Test the PPS class 2 serial data circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs.

Did you find and correct the condition?

Go to Step 13

Go to Step 10

10

Replace the PPS. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 11

--

11

  1. Reconnect all SIR and PPS system components.
  2. Verify that all components, connectors, and connector position assurances (CPAs) are properly mounted.
  3. Use the scan tool in order to clear the SIR and PPS DTCs.
  4. Rezero the PPS. Refer to Passenger Presence System Programming and Setup.
  5. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 12

System OK

12

Replace the SDM. Refer to Control Module References for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 13

--

13

  1. Reconnect all SIR and PPS system components.
  2. Verify that all components, connectors, and CPAs are properly mounted.
  3. Use the scan tool in order to clear the SIR and PPS DTCs.
  4. Rezero the PPS. Refer to Passenger Presence System Programming and Setup.
  5. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 2

System OK