GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2005 🢒 Vibe - FWD 🢒 Restraints 🢒 SIR 🢒 DTC B1615

Circuit Description

The inflatable restraint front end sensor is a crash sensing device used in the detection of a frontal collision. The front end sensor is used by the inflatable restraint sensing and diagnostic module (SDM) to help determine whether or not certain frontal crashes are severe enough to warrant deployment of the frontal air bags. The SDM applies voltage to the sensor - reference circuit and monitors the voltage at the sensor - signal circuit in order to verify proper circuit integrity. If the SDM detects a malfunction within the sensor circuit, a DTC will be set.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B1615 Left Frontal Restraints Sensor

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 inflatable restraint front end sensor - left 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 front end sensor - left circuits
    • A short to ground or voltage in the front end sensor - left circuits
    • A short between the front end sensor - left circuits
    • An internal front end sensor - left malfunction
    • 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. Tests for an open, short to ground, or short to voltage in the front end sensor - left circuits.

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 front end sensor - left connector.
  3. Inspect both the component and harness sides of the 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 3

3

  1. Interchange the front end sensor - left and front end sensor right.
  2. Connect the front end sensor - left and front end sensor right connectors.
  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.

Is DTC 1615 set as a current DTC?

Go to Step 5

Go to Step 4

4

Is DTC 1610 set as a current DTC?

Go to Step 7

Go to Diagnostic Aids

5
  1. Disconnect the sensing and diagnostic module (SDM) connector.
  2. Inspect the SDM connector for the following conditions:
    3. • Corrosion
    • Damaged terminals
    • Poor contact/terminal tension

Did you find and correct the condition?

Go to Step 9

Go to Step 6

6

Test the front end sensor - left - signal and the front end sensor - left - reference circuits for the following conditions:

    • An open or high resistance
    • A short to ground
    • A short between circuits
    • A short to voltage
        Refer to Circuit Testing and Wiring Repairs .

Did you find and correct the condition?

Go to Step 9

Go to Step 8

7

Replace the inflatable restraint front end sensor - left. Refer to Inflatable Restraint Front End Sensor Replacement - Left Side .

Did you complete the replacement?

Go to Step 9

--

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 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 2

System OK