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For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 1999 🢒 Catera 🢒 Restraints 🢒 SIR 🢒 AIR BAG Warning Lamp Comes On Steady

Object Number: 451056 Size: SF
SIR Components
SIR Schematics
SIR Caution
SIR Caution
Handling ESD Sensitive Parts Notice

Circuit Description

When the ignition switch is turned to the ON position, the CLAMP 15 CRUISE Fuse applies battery voltage to the AIR BAG warning lamp that is connected to the INFLATABLE RESTRAINT INDICATOR, terminal 6, of the inflatable restraint sensing and diagnostic and seat belt pretensioner module (SDM). The ignition switch applies battery voltage to the IGNITION input, terminal 5, of the SDM. The SDM responds by flashing the AIR BAG Warning Lamp seven times and then turning it OFF. The SDM monitors the lamp output driver by comparing the output state at the INFLATABLE RESTRAINT INDICATOR, terminal 6, to the microprocessor commanded state.

Diagnostic Aids

In order to disable the shorting bar from terminal 6 to terminal 7 inside the inflatable restraint sensing and diagnostic and seat belt pretensioner module (SDM) wiring harness connector, the SDM wiring harness connector must be properly connected to the SDM.

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 checks to see if either DTC 43 or DTC 44 is present.

    2.

  2. This step checks to see if sufficient voltage is being applied to the SDM.

    3.

  3. This step checks to see if excessive voltage is being applied to the SDM.

    4.

  4. This step checks to see if the connector position assurance (CPA) is properly installed.

    5.

  5. This step checks to see if there is a malfunctioning shorting bar within the SDM wiring harness connector.

    6.

  6. This step checks for a short to ground in CKT XB20.

    7.

  7. This step determines if there is a short between CKT XB20 and CKT X30 or if there is a short to ground in CKT XB20.

    8.

  8. This step checks to see if the SDM wiring harness connector is damaged or corroded.

    9.

  9. This step determines if there is an open or a high resistance in CKT X30 or if there is a malfunctioning SDM.

AIR BAG Warning Lamp Comes On Steady

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 ON position.
  4. Use the scan tool to request the SIR DTC display.

Is either DTC 43 or DTC 44 present?

--

Go to Step 3

Go to Step 4

3
  1. If DTC 43 is present, refer to DTC 43 Warning Lamp Circuit Short to Voltage .
  2. If DTC 44 is present, refer to DTC 44 Warning Lamp Circuit Open or Short to GND .

Is the repair complete?

--

Go to Step 22

--

4

Use the scan tool to request the SIR data list display.

Is the IGNITION more than the specified value?

10 V

Go to Step 5

Go to Step 16

5

  1. Set the parking brake.
  2. Start the engine.
  3. Use the scan tool to request the SIR data list display.

Is the IGNITION more than the specified value?

16 V

Go to Charging System Check in Engine Electrical

Go to Step 6

6

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the inflatable restraint sensing and diagnostic and seat belt pretensioner module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic and Seat Belt Pretensioner Module Replacement .
  3. Inspect the SDM wiring harness connector position assurance (CPA).

Is the SDM CPA properly installed?

--

Go to Step 8

Go to Step 7

7

Properly install the CPA.

Is the repair complete?

--

Go to Step 22

--

8
  1. Disconnect the SDM wiring harness connector. Refer to Inflatable Restraint Sensing and Diagnostic and Seat Belt Pretensioner Module Replacement .
  2. Install the J 42113 SIR Shorting Bar Tool into the SDM wiring harness connector above terminal 6 and terminal 7.
  3. Turn the ignition switch to the ON position.

Does the AIR BAG warning lamp come ON steady?

--

Go to Step 9

Go to Sensing and Diagnostic Module Integrity Check

9

  1. Turn the ignition switch to the OFF position.
  2. Remove the J 42113 SIR Shorting Bar Tool from the SDM wiring harness connector.
  3. Inspect the shorting bar across terminal 6 and terminal 7 within the SDM wiring harness connector.

Is the shorting bar damaged or corroded?

--

Go to Step 10

Go to Step 11

10

Use the J 42250 Catera Terminal Repair Kit to repair the SDM wiring harness connector.

Is the repair complete?

--

Go to Step 22

--

11

  1. Insert the J 42113 SIR Shorting Bar Tool into the SDM wiring harness connector above terminal 6 and terminal 7.
  2. Disconnect the instrument cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gauges and Console.
  3. Use the J 39200 Digital Multimeter (DMM) to measure the resistance between terminal 6 of the SDM wiring harness connector and a known good ground.

Is the measured resistance less than the specified value?

OL

Go to Step 12

Go to Step 15

12

  1. Disconnect CKT F108 from ground G103. Refer to SIR Components .
  2. Use the J 39200 to measure the resistance between terminal 6 and terminal 7 of the SDM wiring harness connector.

Is the measured resistance less than the specified value?

OL

Go to Step 14

Go to Step 13

13
  1. Locate a short to ground in CKT XB20.
  2. Repair the short to ground in CKT XB20.

Is the repair complete?

--

Go to Step 22

--

14
  1. Locate a short between CKT XB20 and CKT F108.
  2. Repair the short between CKT XB20 and CKT F108.
  3. Inspect CKT F108 for cutting or chafing.

Is the repair complete?

--

Go to Step 22

--

15

Replace the instrument cluster. Refer to Instrument Cluster Replacement in Instrument Panel, Gauges and Console.

Is the repair complete?

--

Go to Step 22

--

16

  1. Turn the ignition switch to the OFF position.
  2. Disconnect the inflatable restraint sensing and diagnostic and seat belt pretensioner module (SDM). Refer to Inflatable Restraint Sensing and Diagnostic and Seat Belt Pretensioner Module Replacement .
  3. Inspect terminal 5 of the SDM wiring harness connector for damaged terminals or corrosion.

Is terminal 5 of the SDM wiring harness connector damaged or corroded?

--

Go to Step 17

Go to Step 18

17

Use the J 42250 Catera Terminal Repair Kit to repair the SDM wiring harness connector.

Is the repair complete?

--

Go to Step 22

--

18

Inspect terminal 5 of the SDM for damaged terminals or corrosion.

Is terminal 5 of the SDM damaged or corroded?

--

Go to Step 19

Go to Step 20

19

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

Is the repair complete?

--

Go to Step 22

--

20

  1. Disconnect the ignition switch wiring harness connector. Refer to Ignition Switch Replacement - On Vehicle in Steering Wheel and Column - Tilt.
  2. Use the J 39200J 39200 Digital Multimeter (DMM) to measure the voltage between terminal 5 of the SDM wiring harness connector and terminal V of the ignition switch wiring harness connector.

Is the measured resistance within the specified value?

0-2 ohms

Go to Sensing and Diagnostic Module Integrity Check

Go to Step 21

21
  1. Locate an open or a high resistance in CKT X30.
  2. Repair the open or the high resistance in CKT X30.

Is the repair complete?

--

Go to Step 22

--

22

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

Have all SIR components been reconnected and properly mounted?

--

Go to Step 23

--

23

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

--