Test Description

2001 Chevrolet Chevy Express G2500, Van Passenger Extended, 5.0 MSECTION Test Description
WARNING: This page does not describe the selected car, but rather 10 other vehicles, including the 2001 GMC Yukon XL, 2001 GMC Yukon, 2001 GMC Sierra, 2001 GMC Cab & Chassis Sierra, and 2001 GMC C3500 HD. However, it is still accessible from the selected car via links, so may be relevant.

The number(s) below refer to the step number(s) on the diagnostic table.

  1. Listen for an audible click when the inadvertent power relay operates. Command both the ON and OFF states. Repeat the commands as necessary.

  2. Tests for voltage at the battery positive voltage circuit, coil side, of the inadvertent power relay. The CTSY LP fuse supplies voltage to the coil side of the inadvertent power relay.

  3. Verifies that the body control module is providing ground to the inadvertent power relay.

  4. Tests if ground is constantly being applied to the inadvertent power relay.

  5. Since this is a general circuit malfunction code, it is necessary to test for both a short to voltage as well as an open on this circuit.

DTC B1480

Step Action Yes No
1 Did you perform the Lighting System Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - Lighting Systems 
  1. Install a scan tool.
  2. Turn ON the ignition, with the engine OFF.
  3. With a scan tool, command the inadvertent power relay ON and OFF.
Does the inadvertent power relay turn ON and OFF with each command?
Go to Step 8  Go to Step 3 
  1. Turn OFF the ignition.
  2. Disconnect the inadvertent power relay.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the battery positive voltage circuit, coil side, of the inadvertent power relay and a good ground.
Does the test lamp illuminate?
Go to Step 4  Go to Step 11 
  1. Connect a test lamp between the courtesy lamp control circuit of the inadvertent power relay and the battery positive voltage circuit, coil side, of the inadvertent power relay.
  2. With a scan tool, command the inadvertent power relay ON and OFF .
Does the test lamp turn ON and OFF with each command?
Go to Step 9  Go to Step 5 
Does the test lamp remain illuminated with each command? Go to Step 7  Go to Step 6 
Test the courtesy lamp relay control circuit of the inadvertent power relay for a short to voltage or an open. Refer to Circuit Testing , and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 14  Go to Step 10 
7 Test the courtesy lamp relay control circuit of the inadvertent power relay for a short to ground. Refer to Circuit Testing , and Wiring Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 14  Go to Step 10 
8 Test the courtesy lamps supply voltage circuit between the body control module and the inadvertent power relay for a high resistance or an open.
Did you find and correct the condition?
Go to Step 14  Go to Step 13 
9 Inspect for poor connections at the inadvertent power relay. Refer to Testing for Intermittent Conditions and Poor Connections , and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 14  Go to Step 12 
10 Inspect for poor connections at the harness connector of the body control module. Refer to Testing for Intermittent Conditions and Poor Connections , and Connector Repairs in Wiring Systems.
Did you find and correct the condition?
Go to Step 14  Go to Step 13 
11 Repair the battery positive voltage circuit of the inadvertent power relay. Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?
Go to Step 14  -
12 Replace the inadvertent power relay.
Did you complete the replacement?
Go to Step 14  -
13
IMPORTANT:

Perform the setup procedure for the body control module.

Replace the body control module. Refer to Body Control Module Replacement in Body Control System.Did you complete the replacement?
Go to Step 14  -
14
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?
Go to Step 2  System OK
RENDER: 1.0x

NO RELATED

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When to See a Mechanic

Stop DIY work and contact a certified mechanic immediately if any of the following apply:

  • You smell fuel, burning insulation, or see smoke.
  • Brakes feel soft, pull hard to one side, or make grinding noises.
  • The engine overheats, stalls repeatedly, or misfires under load.
  • You are missing required tools, torque specs, or safe lifting equipment.
  • You are not confident in the next step or safety outcome.