GM Service Manual Online
For 1990-2009 cars only
Makes 🢒 Cadillac 🢒 2005 🢒 STS 🢒 DTC 🢒 DTC B1325

Circuit Description

The inflatable restraint sensing and diagnostic module (SDM) monitors the battery positive voltage input from the battery. If the SDM detects this battery positive voltage circuit is above or below the threshold, then DTC B1325 will set.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B1325 Device Power 1 (low current 1) Circuit

This vehicle has DTCs which include DTC symptoms. For more information on DTC symptoms refer to DTC Symptom Description in Vehicle DTC Information.

Symptom

Symptom Descriptor

03

Voltage below Threshold

07

Voltage above Threshold

Conditions for Running the DTC

The voltage supplied to the SDM is in the range of 9-16 volts.

Conditions for Setting the DTC

B1325 03

    • The SDM detects a system voltage below 9 volts.
    • This condition is present at least 10 seconds.

B1325 07

    • The SDM detects a system voltage above 16 volts.
    • This condition is present at least 10 seconds.

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

Conditions for Clearing the DTC
    • A current DTC clears when the malfunction is no longer present.
    • A history DTC clears when the module ignition cycle counter reaches the reset threshold, without a repeat of the malfunction.

Test Description

The numbers below refer to the step numbers on the diagnostic table.

  1. This checks the voltage from the supply voltage side of the AIR BAG fuse.

  2. This test the battery positive voltage circuit for high or low resistance or an open.

    3.

  3. This test the battery positive voltage circuit for a short to voltage or ground.

Step

Action

Values

Yes

No

Schematic Reference: SIR Schematics

Connector End View Reference: SIR Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

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Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

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

  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, observe the Battery Voltage Input parameters in the SIR input data list.

Is the Battery Voltage Input displayed on the scan tool within the specified range?

9-16 V

Go to Step 3

Go to Step 4

3

Is DTC B1325 set as a history DTC?

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Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

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4

  1. Remove the AIR BAG fuse in the left rear fuse block.
  2. Measure the voltage from the supply voltage side of the AIR BAG fuse to a ground.

Does the voltage measure within the specified value?

9-16 V

Go to Step 5

Go to Charging System Test in Engine Electrical

5
  1. Turn OFF the ignition.
  2. Disconnect the inflatable restraint sensing and diagnostic (SDM) connectors. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.
  3. Inspect the SDM for corrosion or poor connections that may cause a malfunction in the battery positive voltage circuit. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 9

Go to Step 6

6

  1. Turn OFF the ignition.
  2. Test the battery positive voltage circuit between the output side of the AIR BAG fuse and the SDM harness connector for high or low resistance or an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 7

7

  1. Turn ON the ignition, with the engine OFF.
  2. Test the battery positive voltage circuit in the SDM harness connector for a short to voltage or ground. Refer to Circuit Testing and Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

--

Go to Step 9

Go to Step 8

8
  1. Turn OFF the ignition.
  2. Replace the SDM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

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Go to Step 9

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9
  1. Install the AIR BAG fuse and connect all SIR components.
  2. Turn ON the ignition, with the engine OFF.
  3. Use the scan tool in order to clear the DTCs.
  4. Operate the vehicle within the Conditions for Running the DTCs as specified in the supporting text.

Does the DTC reset?

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Go to Step 2

System OK