GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1998 🢒 Seville 🢒 Restraints 🢒 SIR 🢒 DTC B1131 Pass. Pretensioner Loop Resistance High

Object Number: 142291 Size: MF

Circuit Description

When you first turn the ignition switch to the ON position, the inflatable restraint sensing and diagnostic module (SDM) perform tests to diagnose critical malfunctions within itself. Next the SDM measures Ignition 1 and the deployment loop voltages to make sure they are within their respective normal voltage ranges. Then the SDM proceeds with the Resistance Measurement test. During one portion of the Resistance Measurement test, the SDM does the following:

    • Grounds the Passenger Pretensioner Low terminal 11 through an internal current sink.
    • Connects the Passenger Pretensioner High terminal 12 to an internal constant current source. This current produces proportional voltage drops in the deployment loop.
    • Measures the voltage difference between Passenger Pretensioner High and Passenger Pretensioner Low.
    • Calculates the resistance of the passenger pretensioner deployment loop using the measured voltage.

Conditions for Setting the DTC
    • The passenger and driver pretensioner deployment loops are not open.
    • The passenger and driver pretensioner deployment loops are not shorted to voltage.
    • The passenger and driver pretensioner deployment loops are not shorted to ground.
    • The passenger pretensioner deployment loop resistance is more than 3.1 ohms. The passenger pretensioner deployment loop consists of the following components:
       - Passenger seat belt pretensioner.
       - Harness wiring of CKT 2116.
       - Harness wiring of CKT 2117.
       - Connector terminal contact.

The Resistance Measurement test checks for this malfunction. This test only occurs once each ignition cycle when Ignition 1 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 cluster (IPC) to turn ON the AIR BAG warning lamp.

Conditions for Clearing the MIL/DTC
    • Current DTC
        The resistance of the passenger pretensioner deployment loop is less than 3.1 ohms and the ignition switch is cycled.
    • History DTC
       - You issue a scan tool Clear DTCs command.
       - Once 250 malfunction free ignition cycles have occurred.

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

Diagnostic Aids

A poor connection can cause an intermittent condition. Check the following for a poor connection:

    • The side air bag/pretensioner yellow 6-way harness connector terminals A and F.
    • The SDM terminals 12 and 11.
    • The wire to terminal connections in CKT 2116.
    • The wire to terminal connections in CKT 2117.

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 General Electrical Diagnosis Procedures in Wiring Systems. 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 test checks for proper contact or corrosion of the side air bag/pretensioner yellow 6-way connector.

    2.

  2. This test isolates the malfunction to one side of the side air bag/pretensioner yellow 6-way connector.

    3.

  3. This test determines if the malfunction is in the jumper harness or the pretensioner.

    4.

  4. This test checks for proper contact or corrosion of the SDM connector.

    5.

  5. This test determines whether the malfunction is in CKT 2116.

    6.

  6. This test determines whether the malfunction is in CKT 2117.

Step

Action

Value(s)

Yes

No

1

Was the SIR Diagnostic System Check performed?

--

Go to Step 2

Refer to SIR Diagnostic System Check

2

  1. Turn the ignition switch OFF.
  2. Disconnect the passenger side air bag/pretensioner yellow 6-way connector located under the passenger front seat.
  3. Check for proper connection at terminals A and F on the harness side of the passenger side air bag/pretensioner connector.

Are the terminals damaged or corroded?

--

Go to Step 3

Go to Step 5

3

Replace the passenger side air bag/pretensioner yellow 6-way harness connector. Refer to Wiring Repair .

Have the repairs been completed?

--

Go to Step 4

--

4

Check for proper connection at terminals A and F on the passenger side air bag/pretensioner yellow 6-way jumper connector.

Are the terminals damaged or corroded?

--

Go to Step 6

Go to Step 22

5

Check for proper connection at terminals A and F on the passenger side air bag/pretensioner yellow 6-way connector.

Are the terminals damaged or corroded?

--

Go to Step 6

Go to Step 7

6

Replace the passenger seat belt pretensioner jumper harness. Refer to Pretensioner Wiring Harness Replacement .

Have the repairs been completed?

--

Go to Step 22

--

7
  1. Reconnect the passenger side air bag/pretensioner yellow 6-way connector.
  2. Turn the ignition switch to ON.

Is DTC B1131 current?

--

Go to Step 9

Go to Step 8

8
  1. Turn the ignition switch OFF.
  2. Replace the passenger side air bag/pretensioner yellow 6-way harness connector. Refer to Wiring Repair .

Have the repairs been completed?

--

Go to Step 22

--

9

  1. Turn the ignition switch OFF.
  2. Disconnect the passenger side air bag/pretensioner yellow 6-way connector.
  3. Connect the J 38715-A Load Tool to the harness connector.
  4. Turn the ignition switch to ON.

Is DTC B1131 current?

--

Go to Step 13

Go to Step 10

10

  1. Turn the ignition switch OFF.
  2. Disconnect the J 38715-A Load Tool.
  3. Reconnect the passenger side air bag/pretensioner yellow 6-way connector.
  4. Remove the shrink wrap from the passenger seat belt buckle pretensioner.
  5. Disconnect the jumper harness connector from the passenger seat belt buckle pretensioner.
  6. Connect the J 38715-A Load Tool to the jumper harness connector.
  7. Turn the ignition switch to ON.

Is DTC B1131 current?

--

Go to Step 11

Go to Step 12

11
  1. Turn the ignition switch OFF.
  2. Replace the passenger seat belt pretensioner jumper harness. Refer to Wiring Repair .

Have the repairs been completed?

--

Go to Step 22

--

12
  1. Turn the ignition switch OFF.
  2. Replace the passenger seat belt pretensioner. Refer to Seat Belt Buckle Pretensioner Replacement - Right Side .

Have the repairs been completed?

--

Go to Step 22

--

13

  1. Turn the ignition switch OFF.
  2. Disable the frontal SIR and side air bag systems. Refer to Disabling the SIR System .
  3. Disconnect the inflatable restraint Sensing and Diagnostic Module (SDM).
  4. Disconnect the J 38715-A Load Tool.
  5. Check for proper connection at terminals 12 and 11 on the SDM harness connector.

Is the harness connector damaged or corroded?

--

Go to Step 14

Go to Step 16

14

Replace the inflatable restraint sensing and diagnostic module (SDM) harness connector. Refer to Wiring Repair .

Have the repairs been completed?

--

Go to Step 15

--

15

Check for proper connection at terminals 12 and 11 on the SDM.

Are the terminals damaged or corroded?

--

Go to Step 17

Go to Step 22

16

Check for proper connection at terminals 12 and 11 on the SDM.

Are the terminals damaged or corroded?

--

Go to Step 17

Go to Step 18

17

Replace the inflatable restraint sensing and diagnostic module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic Module Replacement .

Have the repairs been completed?

--

Go to Step 22

--

18

Using J 39200 DMM, measure the resistance from the SDM harness connector terminal 12 to the side air bag/pretensioner 6-way harness connector terminal A.

Is the resistance reading within the specified values?

0-0.5 ohms

Go to Step 20

Go to Step 19

19

Repair the high resistance condition in CKT 2116. Refer to Wiring Repair .

Have the repairs been completed?

--

Go to Step 22

--

20

Using J 39200 DMM, measure the resistance from the SDM harness connector terminal 11 to the side air bag/pretensioner 6-way harness connector terminal F.

Is the resistance reading within the specified values?

0-0.5 ohms

Go to Sensing and Diagnostic Module Integrity Check

Go to Step 21

21

Repair the high resistance condition in CKT 2117. Refer to Wiring Repair .

Have the repairs been completed?

--

Go to Step 22

--

22

Reconnect all the SIR components, make sure all the components are properly mounted.

Have all the SIR components been reconnected and properly mounted?

--

Go to Step 23

--

23

Clear all the SIR DTCs. Refer to Diagnostic Trouble Code (DTC) Clearing in Wiring Systems.

Have all the DTCs been cleared?

--

Go to SIR Diagnostic System Check

--