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For 1990-2009 cars only
Makes 🢒 Opel 🢒 1999 🢒 Sintra 🢒 Restraints 🢒 SIR 🢒 DTC B1024 Driver Deployment Loop Short to Ground

Object Number: 417333 Size: SF
SIR Components
SIR Schematics
Handling ESD Sensitive Parts Notice
SIR Caution

Circuit Description

When you first turn the ignition switch to the RUN position, the inflatable restraint sensing and diagnostic module (SDM) performs tests to diagnose critical malfunctions within itself. Upon passing these tests, IGNITION, 23 VLR and the deployment loop voltages are measured to make sure they are within their respective normal voltage ranges. The SDM monitors the voltages at Driver Frontal Low terminal 2 and Passenger Frontal Low terminal 3 to detect shorts to ground in the frontal air bag deployment loop circuits. The service wait time is 10 minutes. Refer to ENABLE/DISABLE procedures.

Conditions for Setting the DTC

    • The driver frontal air bag deployment loop is not open.
    • The driver frontal air bag deployment loop is not shorted to voltage.
    • The voltage at Driver Frontal Low terminal 2 is less than 1.25 volts for 500 milliseconds.

The following tests check for this DTC. These tests occur when IGNITION is within the normal operating voltage range.

    • POWER-ON When the malfunction is detected in this test, the RESISTANCE MEASUREMENT test will not be performed.
    • CONTINUOUS MONITORING

Action Taken When the DTC Sets
    • The SDM sets a DTC B1024.
    • The SDM turns ON the AIR BAG warning lamp.

Conditions for Clearing the DTC
    • Current DTC The voltage at Driver Frontal Low terminal 2 is greater than 2.5 volts for 500 milliseconds.
    • History DTC
       - You issue a scan tool CLEAR CODES command.
       - Once 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

A short to ground in the inflatable restraint steering wheel module circuit can cause an intermittent condition. Inspect CKT 347 and CKT 348 carefully for cutting or chafing. The diagnostic table directs the technician to note the entry value of DRIVER FRONTAL SENSELO. Comparing the value of DRIVER FRONTAL SENSELO can be helpful in determining if an intermittent condition exists.

When measurements are requested in this table, use J 39200 Digital Multimeter with the correct terminal adapter from J 35616 Connector Test Adapter Kit. When a check for proper connection is requested, refer to Intermittents and Poor Connections . When a wire, connector or terminal repair is requested, use J-38125 Terminal Repair Kit and refer to Wiring Repair .

Test Description

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

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

    2.

  2. This step determines if the inflatable restraint steering wheel module or the inflatable restraint steering wheel module coil is defective.

    3.

  3. This step checks for a short to ground in CKT 347.

    4.

  4. This step determines if there is a short to ground in CKT 348 or if there is a malfunctioning SDM.

DTC B1024 Driver Frontal Air Bag Deployment Loop Short to Ground

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. Install the scan tool.
  3. Turn the ignition switch to the RUN position.
  4. Use the scan tool to request the SIR data list display.
  5. Read and record on the repair order the driver frontal air bag low voltage DRIVER FRONTAL SENSELO.

Is the DRIVER FRONTAL SENSELO less than the specified value?

1.25 V

Go to Step 3

Refer to Diagnostic Aids

3

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the inflatable restraint steering wheel module coil and IP module yellow 2-way connectors.
  3. Connect J 38715-A SIR Driver/Passenger Load Tool to the wiring harness connectors.
  4. Turn the ignition switch to the RUN position.
  5. Use the scan tool to request the SIR data list display.
  6. Read the driver frontal air bag low voltage DRIVER FRONTAL SENSELO.

Is DRIVER FRONTAL SENSELO less than the specified value?

1.25 V

Go to Step 7

Go to Step 4

4

  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 J 38715-A from the driver yellow 2-way wiring harness connector.
  4. Connect the driver yellow 2-way connector.
  5. Connect 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.
  7. Use the scan tool to request the SIR data list display.
  8. Read the driver side low voltage DRIVER SENSELO.

Is DRIVER SENSELO less than the specified value?

1.25 V

Go to Step 6

Go to Step 5

5
  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 11

--

6
  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 11

--

7

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the inflatable restraint sensing and diagnostic module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .
  3. Disconnect the J 38715-A .
  4. Insert the J 42113 SIR Shorting Bar Tool into the SDM wiring harness connector above terminal 1 and terminal 2.
  5. Use the J 39200 Digital Multimeter (DMM) to measure the resistance between terminal A of the inflatable restraint steering wheel module coil yellow 2-way wiring harness connector and a known good ground.

Is the measured resistance less than the specified value?

OL

Go to Step 8

Go to Step 9

8
  1. Locate a short to ground in CKT 347.
  2. Repair the short to ground in CKT 347.

Is the repair complete?

--

Go to Step 11

--

9

Use the J 39200 to measure the resistance between terminal B of the inflatable restraint steering wheel module coil yellow 2-way wiring harness connector and a known good ground.

Is the measured resistance less than the specified value?

OL

Go to Step 10

Go to Sensing and Diagnostic Module Integrity Check

10
  1. Locate a short to ground in CKT 348.
  2. Repair the short to ground in CKT 348.

Is the repair complete?

--

Go to Step 11

--

11

Reconnect all the SIR system components, making sure all the components are properly mounted.

Have all the SIR components been reconnected and properly mounted?

--

Go to Step 12

--

12

Use the scan tool to clear all current and history SIR DTCs.

Have all current and history SIR DTCs been cleared?

--

Go to SIR Diagnostic System Check

--