GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Chevrolet 🢒 2008 🢒 Vivant 🢒 HVAC 🢒 HVAC - Automatic 🢒 DTC B0057

Circuit Description

When the ignition switch is turned to ON, the sensing and diagnostic module (SDM) will perform tests to diagnose critical malfunctions within itself.

After passing these tests, ignition and deployment loop voltages are measured to ensure that they are within their respective normal voltage ranges. The SDM then proceeds with the resistance measurement test. Each inflator low terminal is grounded through a current sink, and each inflator current source is connected to each inflator high terminal to allow a known amount of current to flow.

By monitoring the voltage difference between each inflator high and low, the SDM calculates the combined resistance of the inflator module, the wiring harness, and the connector terminal contacts.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B0057 RF Pretensioner Deployment Loop Resistance Low

Conditions for Running the DTC

Ignition voltage is within the normal operating voltage range.

Conditions for Setting the DTC

The resistance of passenger belt pretensioner deployment loop is lower than 1.4 ohms.

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

An intermittent condition likely to be caused by a short between the passenger belt pretensioner high and low circuits.

Step

Action

Values

Yes

No

Caution: Refer to Sensing and Diagnostic Module Voltage after Ignition is Turned Off Caution in the Preface section.

Caution: Refer to Sensing and Diagnostic Module Handling Caution in the Preface section.

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 the ignition OFF.
  2. Wait 1 minute for the sensing and diagnostic module (SDM) capacitor to discharge.
  3. Visually inspect the supplemental inflatable restraint (SIR) wiring harness and connectors.

Is there any visible damage to the SIR harness or connectors?

--

Go to Step 3

Go to Step 4

3

Repair or replace the SIR wiring harness or connectors.

Is the repair complete?

--

Go to Step 8

--

4
  1. Disconnect the electrical connector from the passenger seat belt pretensioner.
  2. Disconnect the electrical connector at the SDM.
  3. Test the resistance between terminal 1 and terminal 2 of the passenger belt pretensioner harness connector.

Is the resistance less than the specified value?

∞

Go to Step 3

Go to Step 5

5

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

Did you complete the replacement?

--

Go to Step 6

--

6
  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 7

System OK

7

Replace the passenger seat belt pretensioner.

Did you complete the replacement?

--

Go to Step 8

--

8
  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