GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2007 🢒 Vibe - FWD 🢒 DTC 🢒 DTC B1655

Circuit Description

The seat belt buckle switch circuit consists of a seat belt buckle switch and the sensing and diagnostic module (SDM). The SDM monitors the seat belt buckle switch for a buckled/unbuckled state. If the SDM detects a malfunction within the seat belt buckle switch circuit, a DTC will be set.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B1655 Driver Seat Belt Sensor Circuit

Conditions for Running the DTC

Ignition 1 voltage is within the normal operating voltage range.

Conditions for Setting the DTC

The SDM detects a malfunction in the seat belt buckle switch circuit.

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 seat belt buckle switch - left circuit
    • A short to ground or voltage in the seat belt buckle switch - left circuit
    • A malfunctioning seat belt buckle switch - left
    • An internal SDM malfunction

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

Test Description

The number below refers to the step number on the diagnostic table.

  1. This step tests for an open, short to ground, or short to voltage in the seat belt buckle switch - left 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. Turn OFF the ignition.
  2. Disconnect the seat belt buckle switch - left 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 3

Go to Step 4

3

  1. If the component side of the seat position sensor connector is damaged, the seat belt buckle - left front must be replaced. Refer to Seat Belt Buckle Replacement - Left Front .
  2. If the harness side of the seat position sensor connector is damaged, replace the harness side of the connector. Refer to Connector Repairs .

Did you complete the replacement?

Go to Step 9

--

4
  1. Turn OFF the ignition.
  2. Disconnect the sensing and diagnostic module (SDM) connector.
  3. Inspect the SDM connector for the following conditions:
    4. • Corrosion
    • Damaged terminals
    • Poor contact/terminal tension

Did you find and correct the condition?

Go to Step 9

Go to Step 5

5

Test the seat belt buckle switch circuit for the following conditions:

    • An open or high resistance
    • A short to ground
    • A short to voltage
        A short between circuits

Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 9

Go to Step 6

6

Replace the seat belt buckle assembly. Refer to Seat Belt Buckle Replacement - Left Front .

Did you complete the replacement?

Go to Step 7

--

7
  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 8

System OK

8

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

Did you complete the replacement?

Go to Step 9

--

9
  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