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For 1990-2009 cars only
Makes 🢒 Oldsmobile 🢒 1999 🢒 Intrigue 🢒 Restraints 🢒 SIR 🢒 DTC B1026 Driver Deployment Loop Open

Object Number: 414967 Size: SF
SIR Components
SIR Schematics
SIR Caution
Handling ESD Sensitive Parts Notice

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. Next the SDM measures IGNITION 1 voltage to make sure it is within its respective normal voltage range. Then the SDM proceeds with the DEPLOYMENT LOOP CONTINUITY test. During the DEPLOYMENT LOOP CONTINUITY test, the SDM measures the voltage difference between DRIVER SIDE HIGH and DRIVER SIDE LOW.

Conditions for Setting the DTC
    • The voltage difference between DRIVER SIDE HIGH terminal 2 and DRIVER SIDE LOW terminal 3 is more than or equal to 400 millivolts.
    • The malfunction must be present for at least 500 milliseconds during one of the following tests:
       - DEPLOYMENT LOOP CONTINUITY
       - If 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 B1026.
    • The SDM turns ON the AIR BAG warning lamp.

Conditions for Clearing the DTC
    • Current DTC
        The voltage difference between DRIVER SIDE HIGH terminal 2 and DRIVER SIDE LOW terminal 3 is less than 400 millivolts for 500 milliseconds.
    • History DTC
       - You issue a scan tool CLEAR CODES command.
       - Once 250 malfunction free ignition cycles have occurred.

Diagnostic Aids

The following can cause an intermittent condition:

    • A poor connection at the inflatable restraint steering wheel module column connector terminal A and terminal B.
    • A poor connection at the upper inflatable restraint steering wheel coil connector terminal A and terminal B.
    • A poor connection at the SDM wiring harness connector terminal 2 and terminal 3.
    • An open in CKT 347.
    • An open in CKT 348.

An intermittent open in the inflatable restraint steering wheel module coil could also set this DTC. To test for a bad inflatable restraint steering wheel module coil, clear the DTC's, then turn the steering wheel back and forth with the ignition switch in the RUN position. If the AIR BAG warning lamp comes ON and DTC B1026 has set again, it is likely the inflatable restraint steering wheel module coil is malfunctioning.

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 step checks the driver deployment loop voltage difference that was measured by the inflatable restraint sensing and diagnostic module (SDM).

    2.

  2. This step checks to see if the inflatable restraint steering wheel module coil yellow 2-way connector is corroded or damaged.

    3.

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

    4.

  4. This step determines if there is a malfunctioning inflatable restraint steering wheel module coil or if there is a malfunctioning inflatable restraint steering wheel module.

    5.

  5. This step checks the SDM wiring harness connector for corrosion or damaged terminals.

    6.

  6. This step checks to see if there is an open in CKT 347.

    7.

  7. This step determines if there is an open in CKT 348 or if there is a malfunctioning SDM.

DTC B1026 Driver Deployment Loop Open

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 scan tool data list.
  5. Read and record on the repair order the driver deployment loop voltage difference DRIVER VDIF.

Has the DRIVER VDIF been read and recorded on the repair order?

--

Go to Step 3

--

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 wiring harness connectors.
  3. Check for a proper connection at terminal A and terminal B on the IP wiring harness side of the inflatable restraint steering wheel module coil yellow 2-way wiring harness connector.

Are the terminals damaged or corroded?

--

Go to Step 4

Go to Step 6

4

Replace the inflatable restraint steering wheel module coil yellow 2-way wiring harness connector. Refer to Wiring Repair .

Is the repair complete?

--

Go to Step 5

--

5

Check for a proper connection at terminal A and terminal B of the inflatable restraint steering wheel module coil yellow 2-way connector.

Are the terminals damaged or corroded?

--

Go to Step 7

Go to Step 23

6

Check for a proper connection at terminal A and terminal B of the inflatable restraint steering wheel module coil yellow 2-way connector.

Are the terminals damaged or corroded?

--

Go to Step 7

Go to Step 8

7

Replace the inflatable restraint steering wheel module coil. Refer to Inflatable Restraint Steering Wheel Module Coil Replacement .

Is the repair complete?

--

Go to Step 23

--

8
  1. Connect the inflatable restraint steering wheel module coil and IP module yellow 2-way wiring harness connectors.
  2. Turn the ignition switch to the RUN position.
  3. Use the scan tool to request the SIR scan tool data list.
  4. Read the driver deployment loop voltage difference DRIVER VDIF.

Is DRIVER VDIF less than the specified value?

400 mV

Go to Step 9

Go to Step 10

9
  1. Turn the ignition switch to the OFF position.
  2. Replace the inflatable restraint steering wheel module coil yellow 2-way wiring harness connector. Refer to Wiring Repair .

Is the repair complete?

--

Go to Step 23

--

10

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

Is DRIVER VDIF less than the specified value?

400 mV

Go to Step 11

Go to Step 14

11

  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 inflatable restraint steering wheel module coil yellow 2-way wiring harness connector.
  4. Connect the inflatable restraint steering wheel module coil 2-way wiring harness connector.
  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.
  7. Use the scan tool to request the SIR scan tool data list.
  8. Read the driver deployment loop voltage difference VDIF.

Is DRIVER VDIF less than the specified value?

400 mV

Go to Step 12

Go to Step 13

12
  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 23

--

13
  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 23

--

14

  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 from the IP wiring harness connectors.
  4. Check for a proper connection at terminal 2 and terminal 3 of the SDM wiring harness connector.

Is the SDM wiring harness connector damaged or corroded?

--

Go to Step 15

Go to Step 17

15

Replace the SDM wiring harness connector. Refer to Wiring Repair .

Is the repair complete?

--

Go to Step 16

--

16

Check for a proper connection at terminal 2 and terminal 3 of the SDM.

Are the SDM terminals damaged or corroded?

--

Go to Step 18

Go to Step 23

17

Check for a proper connection at terminal 2 and terminal 3 of the SDM.

Are the SDM terminals damaged or corroded?

--

Go to Step 18

Go to Step 19

18

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

Is the repair complete?

--

Go to Step 23

--

19

  1. Zero the J 39200 Digital Multimeter (DMM).
  2. Use the J 39200 to measure the resistance between terminal 2 of the SDM wiring harness connector and terminal A of the inflatable restraint steering wheel module coil yellow 2-way wiring harness connector.

Is the measured resistance within the specified value?

0-0.5 ohms

Go to Step 21

Go to Step 20

20
  1. Locate an open in CKT 347.
  2. Repair the open in CKT 347.

Is the repair complete?

--

Go to Step 23

--

21

Use the J 39200 to measure the resistance between terminal 3 of the SDM wiring harness connector and terminal B of the inflatable restraint steering wheel module coil yellow 2-way wiring harness connector.

Is the measured resistance within the specified value?

0-0.5 ohms

Go to Sensing and Diagnostic Module Integrity Check

Go to Step 22

22
  1. Locate an open in CKT 348.
  2. Repair the open in CKT 348.

Is the repair complete?

--

Go to Step 23

--

23

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 24

--

24

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

--