GM Service Manual Online
For 1990-2009 cars only

Object Number: 397602  Size: SF
SIR Components
SIR System Component Description and Definitions
General Service Instructions
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 the SDM. Next the SDM measures IGNITION 1 voltage to ensure that the IGNITION 1 is within the respective normal voltage range for the IGNITION 1. Then the SDM proceeds with the Deployment Loop Continuity test. During the Deployment Loop Continuity test, the SDM measures the voltage difference between PASSENGER SIDE HIGH and PASSENGER SIDE LOW.

Conditions for Setting the DTC

    • The voltage difference between PASSENGER SIDE HIGH terminal 1 and PASSENGER SIDE LOW terminal 4 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 diagnostic trouble code.
    • The SDM turns ON the AIR BAG warning lamp.

Conditions for Clearing the DTC

    • Current DTC
        The voltage difference between PASSENGER SIDE HIGH terminal 1 and PASSENGER SIDE LOW terminal 4 is less than 400 millivolts for 500 milliseconds.
    • History DTC
       - You issue a scan tool CLEAR CODES command.
       - After 250 malfunction free ignition cycles have occurred.

Diagnostic Aids

The following may cause an intermittent condition:

    • A poor connection at the inflatable restraint IP module harness connector terminals A and B
    • A poor connection at the SDM terminals 1 and 4
    • An open in CKT 1403
    • An open in CKT 1404

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 determines the deployment loop voltage difference measured by the inflatable restraint sensing and diagnostic module (SDM).

  2. This test inspects for proper contact or corrosion of the yellow 2-way connector.

  3. This test isolates the malfunction to one side of the inflatable restraint IP module yellow 2-way connector.

  4. This test inspects for proper contact or corrosion of the inflatable restraint IP module jumper connector.

  5. This test determines whether the malfunction is due to the inflatable restraint IP module or the module jumper.

  6. This test inspects for proper contact or corrosion of the SDM harness connector.

  7. This test determines whether the malfunction is in CKT 1403.

  8. This test determines whether the malfunction is in CKT 1404.

DTC B1017 -- Passenger 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. Connect the Scan Tool to the DLC.
  3. Turn the ignition switch to the RUN position.
  4. Request the SIR data list display.
  5. Read and record on the repair order the passenger deployment loop voltage difference PASSENGER VDIF.

Has the PASSENGER 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 and IP module yellow 2-way connectors near the base of the steering column.
  3. Inspect for proper connection at terminals A and B on the IP harness side of the inflatable restraint IP module yellow 2-way jumper connector.

Are the terminals damaged or corroded?

--

Go to Step 4

Go to Step 6

4

Replace the inflatable restraint IP module yellow 2-way IP harness connector. Refer to Wiring Repair .

Is the repair complete?

--

Go to Step 5

--

5

Inspect for proper connection at terminals A and B on the inflatable restraint IP module yellow 2-way jumper connector.

Are the terminals damaged or corroded?

--

Go to Step 7

Go to Step 28

6

Inspect for proper connection at terminals A and B on the inflatable restraint IP module yellow 2-way jumper connector.

Are the terminals damaged or corroded?

--

Go to Step 7

Go to Step 8

7

Repair the inflatable restraint IP module jumper harness. Refer to Wiring Repair .

Is the repair complete?

--

Go to Step 28

--

8

  1. Connect the inflatable restraint steering wheel and IP module yellow 2-way connectors near the base of the steering column.
  2. Turn the ignition switch to the RUN position.
  3. Using the Scan Tool , request the SIR data list display.
  4. Read the passenger deployment loop voltage difference PASSENGER VDIF.

Is the PASSENGER VDIF less than the specified value?

400 mV

Go to Step 9

Go to Step 10

9

  1. Turn the ignition to the OFF position.
  2. Replace the inflatable restraint IP module yellow 2-way IP harness connector. Refer to Wiring Repair .

Is the repair complete?

--

Go to Step 28

--

10

  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.
  3. Connect the J 38715-A SIR Driver/Passenger Load Tool to the connectors.
  4. Turn the ignition switch to the RUN position.
  5. Using the Scan Tool , request the data list display.
  6. Read the passenger deployment loop voltage difference PASSENGER VDIF.

Is the PASSENGER VDIF less than the specified value?

400 mV

Go to Step 11

Go to Step 19

11

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the inflatable restraint IP module pigtail connector from the module jumper.
  3. Inspect for proper connection at terminals A and B of the 2-way jumper connector.

Are the terminals damaged or corroded?

--

Go to Step 12

Go to Step 14

12

Repair the inflatable restraint IP module jumper harness. Refer to Wiring Repair .

Is the repair complete?

--

Go to Step 13

--

13

Inspect for proper connection at terminals A and B on the inflatable restraint IP module yellow 2-way pigtail connector.

Are the terminals damaged or corroded?

--

Go to Step 15

Go to Step 28

14

Inspect for proper connection at terminals A and B on the inflatable restraint IP module yellow 2-way pigtail connector.

Are the terminals damaged or corroded?

--

Go to Step 15

Go to Step 16

15

Replace the inflatable restraint IP module. Refer to Inflatable Restraint Instrument Panel Module Replacement .

Is the repair complete?

--

Go to Step 28

--

16

  1. Disconnect the inflatable restraint IP module jumper harness connector from the J 38715-A .
  2. Connect the connector to the jumper harness.
  3. Connect J 38715-A to the inflatable restraint IP module side of the jumper.
  4. Turn the ignition switch to the RUN position.
  5. Using the Scan Tool , request the SIR data list display.
  6. Read the passenger deployment loop voltage difference PASSENGER VDIF.

Is PASSENGER VDIF less than the specified value?

400 mV

Go to Step 17

Go to Step 18

17

  1. Turn the ignition switch to the OFF position.
  2. Replace the inflatable restraint IP module. Refer to Inflatable Restraint Instrument Panel Module Replacement .

Is the repair complete?

--

Go to Step 28

--

18

  1. Turn the ignition switch to the OFF position.
  2. Repair the high resistance condition in the inflatable restraint IP module jumper harness. Refer to Wiring Repair .

Is the repair complete?

--

Go to Step 28

--

19

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the SDM. Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .
  3. Disconnect the J 38715-A .
  4. Inspect for proper connection at terminals 1 and 4 on the SDM harness connector.

Is the connector damaged or corroded?

--

Go to Step 20

Go to Step 22

20

Replace the SDM harness connector. Refer to Wiring Repair .

Is the repair complete?

--

Go to Step 21

--

21

Inspect for proper connection at terminals 1 and 4 of the SDM.

Are the terminals damaged or corroded?

--

Go to Step 23

Go to Step 28

22

Inspect for proper connection at terminals 1 and 4 of the SDM.

Are the terminals damaged or corroded?

--

Go to Step 23

Go to Step 24

23

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

Is the repair complete?

--

Go to Step 28

--

24

  1. Zero the J 39200 Digital Multimeter.
  2. Measure the resistance from the SDM harness connector terminal 1 to the inflatable restraint IP module yellow 2-way harness connector terminal A.

Is the resistance reading within the specified values?

0-0.5 ohms

Go to Step 26

Go to Step 25

25

Repair the high resistance condition in CKT 1403.

Is the repair complete?

--

Go to Step 28

--

26

Measure the resistance from the SDM harness connector terminal 4 to the inflatable restraint IP module yellow 2-way harness connector terminal B.

Is the resistance reading within the specified values?

0-0.5 ohms

Go to Sensing and Diagnostic Module Integrity Check

Go to Step 27

27

Repair the high resistance condition in CKT 1404.

Is the repair complete?

--

Go to Step 28

--

28

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

Have all the SIR components been reconnected and properly mounted?

--

Go to Step 29

--

29

Clear all the SIR DTCs.

Have all the SIR DTCs been cleared?

--

Go to SIR Diagnostic System Check

--