GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Buick 🢒 1999 🢒 Park Avenue 🢒 DTC 🢒 DTC B1122 Driver Deployment Loop Resistance Low

Object Number: 397195 Size: MF
SIR Components
SIR System Operation
SIR Handling Caution
Handling ESD Sensitive Parts Notice
SIR Schematic Icons
SIR Schematic Icons

Circuit Description

When you first turn the ignition switch to the RUN position, the inflatable restraint sensing and diagnostic module (SDM) performs tests in order to diagnose critical malfunctions within the module. Next the SDM measures the ignition positive voltage and the deployment loop voltages in order to ensure that the voltages are within their respective normal voltage ranges. The SDM proceeds with the RESISTANCE MEASUREMENT test. During 1 portion of the RESISTANCE MEASUREMENT test, the SDM performs the following functions:

    • Grounds the DRIVER LOW terminal 9 through an internal current sink
    • Connects the DRIVER HIGH terminal 10 to an internal constant current source. This current produces proportional voltage drops in the deployment loop.
    • Measures the voltage difference between DRIVER HIGH and DRIVER LOW
    • Calculates the resistance of the driver deployment loop using the measured voltage

Conditions for Setting the DTC
    • The driver and passenger deployment loops are not open.
    • The driver and passenger deployment loops are not shorted to voltage.
    • The driver and passenger deployment loops are not shorted to ground.
    • The driver deployment loop resistance is less than 1.7 ohms. The driver deployment loop consists of the following components:
       - An inflatable restraint steering wheel module
       - An inflatable restraint steering wheel module coil
       - Harness wiring of CKT 347
       - Harness wiring of CKT 348
       - Connector terminal contact

The RESISTANCE MEASUREMENT test inspects for this malfunction. This test only occurs once each ignition cycle when ignition positive voltage is within the normal operating voltage range.

Action Taken When the DTC Sets
    • The SDM sets a diagnostic trouble code (DTC).
    • The SDM commands the instrument panel cluster (IPC) in order to turn ON the AIR BAG warning lamp.

Conditions for Clearing the MIL/DTC

The DTC will clear when one of the following conditions is met:

    • Current DTC
        The resistance of the driver deployment loop is more than 1.7 ohms and the ignition switch is cycled.
    • History DTC
       - You issue a scan tool CLEAR CODES command.
       - 250 malfunction free ignition cycles have occurred.

When you issue a scan tool CLEAR CODES command and the malfunction is still present, the DTC will not reappear until the next ignition cycle.

Diagnostic Aids

The following conditions may cause an intermittent condition:

    • A short circuit between CKT 347 and CKT 348
    • A short circuit between CKT 347 and CKT 1403
    • A short circuit between CKT 347 and CKT 1404
    • A malfunctioning shorting bar on the inflatable restraint steering wheel module connector
    • A malfunctioning shorting bar on the inflatable restraint steering wheel module coil steering column connector

When measurements are requested in this table, use the J 39200 DMM with the correct terminal adapter from the J 35616 Connector Test Adapter Kit. When an inspection for proper connection is requested, refer to Testing for Electrical Intermittents in Wiring Systems. When a wire, connector or terminal repair is requested, use the J-38125 Terminal Repair Kit and refer to Wiring Repairs in Wiring Systems.

Test Description

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

  1. This test inspects for a short from CKT 1403 to CKT 347.

    2.

  2. This test isolates the malfunction to one side of the inflatable restraint steering wheel module coil yellow 2-way connector.

    3.

  3. This test determines whether the malfunction is due to the inflatable restraint steering wheel module or the module coil.

    4.

  4. This test inspects for a short from CKT 347 to CKT 348.

    5.

  5. This test inspects for a short from CKT 347 to CKT 1404.

Step

Action

Value(s)

Yes

No

1

Was the SIR Diagnostic System Check performed?

--

Go to Step 2

Go to SIR Diagnostic System Check

2

  1. Turn the ignition switch to the OFF position.
  2. Connect a scan tool to the DLC.
  3. Turn the ignition switch to the RUN position.
  4. Request the SIR DTC display.

Is DTC B1116 also present?

--

Go to Step 3

Go to Step 4

3
  1. Turn the ignition switch to the OFF position.
  2. Disconnect the inflatable restraint steering wheel and IP module yellow 2-way connectors at the base of the steering column and above the right side of the sound insulator.
  3. Repair the short from CKT 347 to CKT 1403. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 13

--

4

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the inflatable restraint steering wheel module yellow 2-way connector at the base of the steering column and above the right side of the sound insulator.
  3. Reconnect the 2-way connector.
  4. Inspect that the CPA is properly installed.
  5. Turn the ignition switch to the RUN position.
  6. Use a scan tool in order to request the SIR DTC display.

Is DTC B1122 current?

--

Go to Step 5

Go to Step 13

5

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the inflatable restraint steering wheel and IP module yellow 2-way connectors at the base of the steering column and above the right side of the sound insulator.
  3. Connect the J 38715-A to the harness connectors.
  4. Turn the ignition switch to the RUN position.

Is DTC B1122 current?

--

Go to Step 9

Go to Step 6

6
  1. Turn the ignition switch to the OFF position.
  2. Remove the inflatable restraint steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement .
  3. Disconnect the J 38715-A from the driver 2-way connector.
  4. Connect the 2-way connector at the base of the steering column.
  5. Connect the J 38715-A to the upper inflatable restraint steering wheel module coil connector on the steering column.
  6. Turn the ignition switch to the RUN position.

Is DTC B1122 current?

--

Go to Step 8

Go to Step 7

7
  1. Turn the ignition switch to the OFF position.
  2. Replace the inflatable restraint steering wheel module. Refer to Inflatable Restraint Steering Wheel Module Replacement .

Is the repair complete?

--

Go to Step 13

--

8
  1. Turn the ignition switch to the OFF position.
  2. Replace the inflatable restraint steering wheel module coil. Refer to Inflatable Restraint Steering Wheel Module Coil Replacement .

Is the repair complete?

--

Go to Step 13

--

9

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the inflatable restraint sensing and diagnostic module (SDM).
  3. Disconnect the J 38715-A .
  4. Measure the resistance from the SDM harness connector terminal 10 to terminal 9.

Is the resistance reading less than the specified value?

OL

Go to Step 10

Go to Step 11

10

Repair a short from CKT 347 to CKT 348. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 13

--

11

Measure the resistance from the SDM harness connector terminal 10 to terminal 8.

Is the resistance reading less than the specified value?

OL

Go to Step 12

Go to Sensing and Diagnostic Module Integrity Check

12

Repair a short from CKT 347 to CKT 1404. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

--

Go to Step 13

--

13

Reconnect all the SIR system components. Ensure that all the components are properly mounted.

Have all the SIR components been reconnected and properly mounted?

--

Go to Step 14

--

14

Clear all the SIR DTCs.

Have all the SIR DTCs been cleared?

--

Go to SIR Diagnostic System Check

--