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 occupant's 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 occupant's 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 rearview mirror. 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 DTC B0092 and requesting the instrument panel cluster (IPC) to turn the AIR BAG indicator ON.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC 065 PPS Sensor Circuit Out of Range

Conditions for Running the DTC

Ignition 1 voltage is within the normal operating voltage range.

Conditions for Setting the DTC

    • The PPS detects the voltage at PPS sensor signal is less than 0.05 volts or greater than 4.5 volts for 500 milliseconds.
    • The PPS detects the voltage at 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 PPS sensor low reference is 25 mA or greater for 500 milliseconds.

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

The following can cause an intermittent condition:

    • A short between the PPS sensor signal, 5-volt reference, and low reference circuits
    • An open or high resistance between the PPS sensor signal, 5-volt reference, and low reference circuits
    • Inspect the PPS sensor signal, 5-volt reference, and low reference circuits carefully for cutting and/or chafing

Refer to Testing for Intermittent Conditions and Poor Connections in Wiring Systems.

Test Description

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

  1. This step inspects the PPS pressure sensor connector.

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

  3. This step tests for a short to ground, a high resistance, or an open in the PPS sensor 5-volt reference circuit.

  4. This step tests for a short to ground, a high resistance, or an open in the PPS sensor low reference circuit.

  5. This step tests for a short to voltage in the PPS sensor signal circuit.

  6. This step tests the PPS sensor signal circuit input voltage range.

  7. This step tests for a short to voltage in the PPS sensor 5-volt reference circuit.

  8. This step tests for a short to voltage in the PPS sensor low reference circuit.

Step

Action

Value(s)

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 in Vehicle DTC Information

2

  1. Turn OFF the ignition.
  2. Disconnect the passenger presence system (PPS) pressure sensor connector. Refer to Inflatable Restraint Passenger Presence System Replacement - Front .
  3. Inspect the pressure sensor terminals and harness connector for damage or corrosion.

Do the PPS pressure sensor terminals or the harness connector exhibit any signs of damage or corrosion?

--

Go to Step 3

Go to Step 4

3

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

Did you complete the replacement?

--

Go to Step 13

--

4

  1. Disconnect the PPS module connector. Refer to Inflatable Restraint Passenger Presence System Replacement - Front .
  2. Inspect the PPS module connector for corrosion or damage. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 5

5

Test the PPS sensor signal circuit for a short to ground, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 6

6

Test the PPS sensor 5-volt reference circuit for a short to ground, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 7

7

Test the PPS sensor low reference circuit for a short to ground, a high resistance, or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 8

8

  1. Turn ON the ignition, with the engine OFF.
  2. Test the PPS sensor signal circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 9

9

Test the PPS sensor signal circuit input voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Does the voltage measure within the specified range?

0.05-4.5 V

Go to Step 10

Go to Step 12

10

Test the PPS sensor 5-volt reference circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 11

11

Test the PPS sensor low reference circuit for a short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 12

12

Replace the PPS. Refer to Control Module References in Computer/Integrating Systems 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 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 in 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