GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2006 🢒 Vibe - AWD 🢒 Restraints 🢒 SIR 🢒 DTC B1780

Circuit Description

The passenger presence system (PPS) sensor - left front circuit consists of the PPS sensor - left front and the PPS module. The PPS module monitors the PPS sensor - left front. If the sensing and diagnostic module (SDM) detects a malfunction within the sensor - left front circuit, a DTC will be set.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B1780 Passenger Presence Sensor - Left Front

Conditions for Running the DTC

Ignition 1 voltage is within the normal operating voltage range.

Conditions for Setting the DTC

The SDM detects a PPS sensor - left front malfunction.

Action Taken When the DTC Sets

The SDM commands the AIR BAG indicator ON.

Conditions for Clearing the DTC

The condition responsible for setting the DTC no longer exists and the scan tool Clear DTCs function is used.

Diagnostic Aids

Thoroughly inspect the wiring and the connectors. An incomplete inspection of the wiring and the connectors may result in a misdiagnosis, causing a part replacement with the reappearance of the malfunction.

The following are possible causes of the malfunction:

    • An open or high resistance in the PPS sensor - left front circuit
    • A short to ground or voltage in the PPS sensor - left front circuit
    • A short between the PPS sensor - left front circuits
    • A malfunctioning PPS sensor - left front
    • An internal PPS module malfunction

If an intermittent malfunction exists, refer to Testing for Intermittent Conditions and Poor Connections .

Test Description

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

  1. Tests the PPS sensor - left front circuits for an open or high resistance.

    Tests the PPS sensor - left front circuits for a short to ground.

    Tests the PPS sensor - left front circuits for a short to voltage.

    2.

  2. Tests to see if the malfunction is caused by the PPS sensor - left front.

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

Is DTC B1780 set as a current DTC?

Go to Step 3

Go to Diagnostic Aids

3
  1. Turn OFF the ignition.
  2. Disconnect the passenger presence system (PPS) sensor - left front connector.
  3. Inspect both the component and harness sides of the connector for damage or corrosion that may cause the malfunction. Refer to Testing for Intermittent Conditions and Poor Connections .

Does the connector exhibit any signs of damage or corrosion?

Go to Step 4

Go to Step 5

4
  1. If the component side of the PPS sensor - left front connector is damaged, the PPS sensor - left front must be replaced. Refer to Front Seat Adjuster Replacement .
  2. If the harness side of the PPS sensor - left front connector is damaged, replace the harness side of the connector. Refer to Connector Repairs .

Did you complete the replacement?

Go to Step 10

--

5
  1. Turn OFF the ignition.
  2. Disconnect the PPS module connector.
  3. Inspect the PPS module connector for the following conditions:
    4. • Corrosion
    • Damaged terminals
    • Poor contact/terminal tension

Did you find and correct the condition?

Go to Step 10

Go to Step 6

6

  1. Test the PPS sensor - left front circuits for an open or high resistance.
  2. Test the PPS sensor - left front circuits for a short to ground.
  3. Test the PPS sensor - left front circuits for a short to voltage.
  4. Test the PPS sensor - left front circuits for a short between circuits.
  5. All the above conditions refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 10

Go to Step 7

7

Replace the PPS module. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .

Did you complete the replacement?

Go to Step 8

--

8

  1. Reconnect all SIR 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 DTCs.
  4. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.

Does the DTC reset?

Go to Step 9

System OK

9

Replace the PPS sensor - left front. Refer to Front Seat Adjuster Replacement .

Did you complete the replacement?

Go to Step 10

--

10
  1. Reconnect all SIR components.
  2. Verify that all components, connectors, and CPAs are properly mounted.
  3. Use the scan tool in order to Clear the DTCs.
  4. 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