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Test Description

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

  1. 2:  Listen for an audible click when the Door Unlock Relay operates. Command both the ON and OFF states. Repeat the commands as necessary.
  2. 3:  Verifies that the Body Control Module (BCM) is providing voltage to the door unlock relay.
  3. 4:  Tests for an open in the ground circuit to the door unlock relay.
  4. 5:  Tests if voltage is constantly being applied to the door unlock relay.
  5. 12:  After replacement of the BCM you must calibrate the new module for proper operation.
DTC B3147 or B3148

Step Action Yes No
Schematic Reference: Door Lock/Indicator Schematics 
1 Did you perform the Power Door Systems Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - Door Systems 
2 
  1. Install a scan tool.
  2. With a scan tool, command the door unlock relay ON and OFF.
Does the door unlock relay turn ON and OFF with each command?		 Go to TESTING FOR INTERMITTENT AND POOR CONNECTIONS Go to Step 3 
3 
  1. Remove the door unlock relay.
  2. Probe the door unlock control circuit of the door unlock relay with a test lamp that is connected to a good ground.
  3. With a scan tool, command the door unlock relay ON and OFF.
Does the test lamp turn ON and OFF with each command?		 Go to Step 4  Go to Step 5 
4 
  1. Connect a test lamp between the door unlock control circuit and the ground circuit of the door unlock relay.
  2. With a scan tool, command the door unlock relay ON and OFF.
Does the test lamp turn ON and OFF with each command?		 Go to Step 8  Go to Step 10 
5  Does the test lamp remain illuminated with each command? Go to Step 7  Go to Step 6 
6 Test the door unlock control circuit of the door unlock relay for a short to ground. Refer to CIRCUIT TESTING and WIRING REPAIRS .
Did you find and correct the condition?		 Go to Step 13  Go to Step 9 
7 Test the door unlock control circuit of the door unlock relay for a short to voltage. Refer to CIRCUIT TESTING and WIRING REPAIRS .
Did you find and correct the condition?		 Go to Step 13  Go to Step 9 
8 Inspect for poor connections at the door unlock relay. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS and CONNECTOR REPAIRS .
Did you find and correct the condition?		 Go to Step 13  Go to Step 11 
9 Inspect for poor connections at the harness connector of the BCM. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS and CONNECTOR REPAIRS .
Did you find and correct the condition?		 Go to Step 13  Go to Step 12 
10 Repair the ground circuit of the door unlock relay. Refer to WIRING REPAIRS .
Did you complete the repair?		 Go to Step 13  -
11 Replace the door unlock relay.
Did you complete the replacement?		 Go to Step 13  -
12  Replace the BCM. Refer to BODY CONTROL MODULE REPLACEMENT .
Did you complete the replacement?		 Go to Step 13  -
13
  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
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