GM Service Manual Online
For 1990-2009 cars only

Object Number: 39360  Size: LF

Circuit Description

During the normal, non-deployment operation of the SIR system, a small amount of current flows through the driver deployment loop. The diagnostic resistors within the inflatable restraint arming sensor and the inflatable restraint discriminating sensors along with the resistance of the inflatable restraint steering wheel inflator module cause voltage drops within the deployment loop. The inflatable restraint Diagnostic Energy Reserve Module (DERM) monitors the voltage at the Driver Side Low terminal B8 to detect shorts or opens within the deployment loop. When the measured voltage is within a specified percentage of the Driver 36 VLR power supply for 500 milliseconds, DTC B1035 is set.

Conditions for Setting the DTC

During continuous monitoring, the voltage measured at the Driver Side Low terminal B8 is within a specified percentage of the Driver 36 VLR power supply voltage for 500 milliseconds .

Action Taken When the DTC Sets

The DERM turns on the AIR BAG warning lamp and sets a diagnostic trouble code.

Conditions for Clearing the DTC

The voltage measured at the Driver Side Low terminal B8 is above or below the percentage of the Driver 36 VLR power supply voltage which sets DTC B1035.

Diagnostic Aids

An intermittent condition may be caused by one of the following:

    • An improper connection at any of the inflatable restraint discriminating sensor terminals
    • An open in one of the ground feeds to the inflatable restraint discriminating sensors
    • An open inflatable restraint discriminating sensor interconnect circuit
    • An increased resistance of one of the inflatable restraint discriminating sensors
    • A decreased resistance of the inflatable restraint arming sensor

Test Description

  1. Start at the SIR Diagnostic System Check for all diagnosis.

  2. This test checks for increased resistance of the LH forward inflatable restraint discriminating sensor.

  3. This test checks for an open in the ground feed to the LH forward inflatable restraint discriminating sensor.

  4. This test locates the open in the ground feed to the LH forward inflatable restraint discriminating sensor.

  5. This test checks for increased resistance of the RH forward inflatable restraint discriminating sensor.

  6. This test checks for an open in the ground feed to the RH forward inflatable restraint discriminating sensor.

  7. This test locates the open in the ground feed to the RH forward inflatable restraint discriminating sensor.

  8. This test checks for an open in the inflatable restraint discriminating sensor interconnect circuit.

  9. This test checks for a malfunctioning inflatable restraint arming sensor.

When measurements are requested in this chart use J 39200 Digital Multimeter with correct terminal adapter from J 35616 Connector Test Adapter Kit. When a check for proper connection is requested, refer to Intermittents and Poor Connections in Section 8A4. When a wire, connector or terminal repair is requested, use J-38125 Terminal Repair Kit and refer to Wiring Repair.

DTC B1035- Infl Rst Disc Sensor Open or Missing

Step

Action

Value

Yes

No

1

Was the SIR Diagnostic System Check performed?

--

Go to Step 2

Go to SIR Diagnostic System Check

2

  1. Disconnect the yellow 2-way connector C214 at the base of the steering column.
  2. Disconnect the LH forward inflatable restraint discriminating sensor.
  3. Check for proper connection to the LH forward inflatable restraint discriminating sensor at terminals A, B and C.

Is the LH forward inflatable restraint discriminating sensor electrical harness connector damaged or corroded?

--

Go to Step 3

Go to Step 5

3

Repair the LH forward inflatable restraint discriminating sensor electrical harness connector.

Has the connector been repaired?

--

Go to Step 4

--

4

Check for proper connection to LH forward inflatable restraint discriminating sensor at the terminals A, B, and C.

Are the LH forward inflatable restraint discriminating sensor terminals damaged or corroded?

--

Go to Step 6

Go to Step 31

5

Check for proper connection to LH forward inflatable restraint discriminating sensor.

Are the LH forward inflatable restraint discriminating sensor terminals damaged or corroded?

--

Go to Step 6

Go to Step 7

6

Replace the LH forward inflatable restraint discriminating sensor. Refer to Inflatable Restraint Front End Discriminating Sensor .

Has the sensor been replaced?

--

Go to Step 31

--

7

Measure the resistance on the LH Forward Discriminating terminal B to C.

Is the resistance more than the specified value?

8.54 kohms

Go to Step 6

Go to Step 8

8

Measure the resistance from the LH Forward Discriminating electrical harness connector terminal C to ground.

Is the resistance less than the specified value?

5 ohms

Go to Step 14

Go to Step 9

9

  1. Disconnect the inflatable restraint discriminating sensor intermediate harness electrical connector C109.
  2. Check for proper connection of the inflatable restraint discriminating sensor intermediate harness electrical connector C109 at terminal B.

Is the inflatable restraint discriminating sensor intermediate harness electrical connector damaged or corroded?

--

Go to Step 10

Go to Step 11

10

  1. Repair the inflatable restraint discriminating sensor intermediate harness electrical connector C109.
  2. Has the connector been repaired?

--

Go to Step 31

--

11

Measure the resistance of circuit 1751 from the LH forward inflatable restraint discriminating sensor harness electrical connector terminal C to the inflatable restraint discriminating sensor intermediate harness connector C109 terminal B.

Is the resistance less than the specified value?

5 ohms

Go to Step 12

Go to Step 13

12

Repair the open in circuit 1751 between C109 and S233.

Has the open circuit been repaired?

--

Go to Step 31

--

13

Repair the open in circuit 1751 between the inflatable restraint discriminating sensor intermediate harness connector C109.

Has the open circuit been repaired?

--

Go to Step 31

--

14

  1. Disconnect the RH forward inflatable restraint discriminating sensor.
  2. Check for proper connection to the RH forward inflatable restraint discriminating sensor at terminals A and B.

Is the RH forward inflatable restraint discriminating sensor electrical harness connector damaged or corroded?

--

Go to Step 15

Go to Step 17

15

Replace the RH Forward inflatable restraint arming sensor jumper harness electrical connector.

Has the connector been replaced?

--

Go to Step 16

--

16

Check for proper connection to the RH forward inflatable restraint discriminating sensor.

Are the RH forward inflatable restraint discriminating sensor electrical harness connector damaged or corroded?

--

Go to Step 18

Go to Step 31

17

Check for proper connection to the RH forward inflatable restraint discriminating sensor.

Are the RH forward inflatable restraint discriminating sensor terminals damaged or corroded?

--

Go to Step 18

Go to Step 19

18

Replace the RH forward inflatable restraint discriminating sensor. Refer to Inflatable Restraint Front End Discriminating Sensor .

Has the sensor been replaced?

--

Go to Step 31

--

19

Measure the resistance on the RH forward inflatable restraint discriminating sensor electrical connector from terminal A to terminal B.

Is the resistance more than the specified value?

8.54 kohms

Go to Step 20

Go to Step 21

20

Replace the RH forward inflatable restraint discriminating sensor. Refer to Inflatable Restraint Front End Discriminating Sensor .

Has the sensor been replaced?

--

Go to Step 31

--

21

Measure the resistance from the RH forward inflatable restraint discriminating sensor electrical harness connector terminal B to ground.

Is the resistance less than the specified value?

5 ohms

Go to Step 27

Go to Step 22

22

  1. Disconnect the inflatable restraint discriminating sensor intermediate harness electrical connector C109.
  2. Check for proper connection of the inflatable restraint discriminating sensor intermediate harness electrical connector C109 terminal C.

Is the inflatable restraint discriminating sensor intermediate harness electrical connector damaged or corroded?

--

Go to Step 23

Go to Step 24

23

Repair the inflatable restraint discriminating sensor intermediate harness electrical connector C109.

Has the connector been repaired?

--

Go to Step 31

--

24

Measure the resistance of circuit 1751 from the RH forward inflatable restraint discriminating sensor electrical harness connector terminal B to the Discriminating Sensor intermediate harness electrical connector C109 terminal C.

Is the resistance less than the specified value?

5 ohms

Go to Step 25

Go to Step 26

25

Repair the open in circuit 1751 between C109 and S233.

Has the open circuit been repaired?

--

Go to Step 31

--

26

Repair the open in circuit 1751 in the inflatable restraint discriminating sensor intermediate harness electrical connector C109.

Has the open circuit been repaired?

--

Go to Step 31

--

27

Measure the resistance of circuit 349 from the RH forward inflatable restraint discriminating sensor electrical harness connector terminal A to the LH forward inflatable restraint discriminating sensor electrical harness connector terminal B.

Is the resistance less than the value specified?

5 ohms

Go to Step 29

Go to Step 28

28

Repair the open in circuit 349.

Has the open circuit been repaired?

--

Go to Step 31

--

29

  1. Disconnect the inflatable restraint arming sensor.
  2. Measure the resistance on the inflatable restraint arming sensor from terminal C to terminal D.

Is the resistance less than the value specified?

7.5 kohms

Go to Step 30

Go to Integrity Check

30

Replace the inflatable restraint arming sensor. Refer to Inflatable Restraint Arming Sensor .

Has the sensor been replaced?

--

Go to Step 31

--

31

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

Have all the SIR components been reconnected and properly mounted?

--

Go to Step 32

--

32

Clear the SIR Diagnostic Trouble Codes.

Have the SIR Diagnostic Trouble Codes been cleared?

--

Go to SIR Diagnostic System Check

--