GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2009 🢒 SLS 🢒 Safety and Security 🢒 Supplemental Inflatable Restraints 🢒 DTC B1325

Circuit Description

Inflatable Restraint Sensing and Diagnostic module (SDM) monitors the positive voltage input from the battery. If the SDM detects the positive voltage of the battery is higher or lower than the threshold, DTC B1325 sets.

DTC Descriptor

The diagnostic procedure supports the following DTC:

DTC B1325 Equipment Power 1 (Low Current 1) Circuit

The vehicle has DTCs including the DTC symptoms. Refer to DTC Symptom Description for more DTC information.

DTC Symptom

DTC Symptom Descriptor

03

Voltage below threshold

07

Voltage above threshold

Conditions for Running the DTC

Voltage of the SDM is between 9-16 volts.

Conditions for Setting the DTC

B1325 03

    • The detected SDM system voltage is lower than 9 V.
    • It lasts for 10 seconds.

B1325 07

    • The detected SDM system voltage is more than 16 V.
    • It lasts for 10 seconds.

Actions Taken When the DTC Sets
    • The SDM commands the AIR BAG indicator ON via GMLAN serial data communications.
    • The SDM stores the DTC into the memory.

Conditions for Clearing the DTC
    • The current DTC will be cleared away after the trouble is removed.
    • When the ignition cycle counter has reached the newly set threshold and no trouble occurs repeatedly, the history DTC will be cleared.

Test Description

The following numbers are corresponding to the steps in the diagnostic table.

  1. This step tests the voltage of the airbag fuse.

    2.

  2. This step tests if the battery positive voltage circuit has high or low resistance or is open.

    3.

  3. This step tests if the battery positive voltage circuit is short to voltage or ground.

Step

Action

Value

Yes

No

Schematic Reference: SIR Schematics

Connector End View Reference: SIR Connector End Views

1

Have you conducted Diagnostic System Check - Vehicle?

--

Go to Step 2

Go to Diagnostic System Check - Vehicle

2

Important: J-45289 CANdi Module must be used together with the scan tool.

  1. Install the scan tool.
  2. Engine off, ignition on.
  3. Use scan tool to observe the Battery Voltage Input parameters in the SIR scan tool data list.

Does the scan tool indicate the battery voltage input is within the specified range?

9-16 V

Go to Step 3

Go to Step 4

3

Is DTC B1325 set as history DTC?

--

Go to Testing for Intermittent Conditions and Poor Connections

--

4

  1. Remove the airbag fuse from the left rear fusebox.
  2. Measure the voltage between the airbag fuse signal and ground.

Is the measured voltage within the specified value?

9-16 V

Go to Step 5

Go to Inflation System Test

5
  1. Turn the ignition switch to OFF position.
  2. Disconnect the SIR system sensing and diagnostic module (SDM) connector. Refer to Control Module References for replacement, set up, and programming.
  3. Check if the SDM has corrosion or poor connections that may result in battery positive voltage circuit fault. Refer to Testing for Intermittent Conditions and Poor Connections .

Do you find and correct the condition?

--

Go to Step 9

Go to Step 6

6

  1. Turn the ignition switch to OFF position.
  2. Test if the battery positive voltage circuit between the airbag fuse output and SDM harness connector has high or low resistance or is open. Refer to Circuit Testing .

Do you find and correct the condition?

--

Go to Step 9

Go to Step 7

7

  1. Engine off, ignition on.
  2. This step tests if the battery positive voltage circuit between SDM harness connector is short to voltage or ground. Refer to Circuit Testing .

Do you find and correct the condition?

--

Go to Step 9

Go to Step 8

8
  1. Turn the ignition switch to OFF position.
  2. Replace the SDM module. Refer to Control Module References for replacement, set up, and programming.

Have you finished the replacement?

--

Go to Step 9

--

9
  1. Install the airbag fuses and connect all airbag components.
  2. Engine off, ignition on.
  3. Clear away all DTCs with scan tool.
  4. Operate the vehicle under conditions when DTC runs as specified in supporting documents.

Does the DTC set again?

--

Go to Step 2

SystemOK