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Home >> Pontiac >> 2001 >> Aztek Base, AWD >> Repair and Diagnosis >> External Pages >> Different car >> Section 1468 (Mirror System & Window System) >> Diagnostic Information and Procedures >> DTC B0285: Open Or Short To Ground In The Rear Defog Relay Control Circuit >> Test Description
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Test Description

WARNING: This page is about a different car, the 2003 Saturn Vue. However, it is still accessible from the selected car via links, so may be relevant.

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

  1. 2:  Listen for an audible click when the REAR DEFOG relay operates. Command both the on and off states. Repeat the commands as necessary.
  2. 3:  Verifies that the BCM is providing ground input to the REAR DEFOG relay.
  3. 5:  Tests for a short to ground on the rear defog relay control circuit of the REAR DEFOG relay coil.
DTC B0285

Step Action Yes No
Connector End View Reference: Master Electrical Component List in Wiring Systems
1 Did you perform the Defogger Diagnostic System Check? Go to Step 2  Go to Diagnostic System Check - Defogger 
2 
  1. Turn ON the ignition, with the engine OFF.
  2. With a scan tool select from special functions, the Rear Defogger Relay from the BCM output controls.
  3. Command the REAR DEFOG relay ON and OFF.
Do you hear a click when you command the REAR DEFOG relay ON and OFF?		 Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems Go to Step 3 
3 
  1. Turn OFF the ignition.
  2. Disconnect the REAR DEFOG relay.
  3. Turn ON the ignition, with the engine OFF.
  4. Connect a test lamp between the rear defog relay control circuit of the REAR DEFOG relay coil and B+.
  5. With a scan tool, command the REAR DEFOG 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 supply voltage circuit of the REAR DEFOG relay and the rear defog relay control circuit of the REAR DEFOG relay coil.
  2. With a scan tool, command the REAR DEFOG relay ON and OFF.
Does the test lamp turn ON and OFF with each command?		 Go to Step 7  Go to Step 9 
5  Test the rear defog relay control circuit of the REAR DEFOG 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 12  Go to Step 6 
6 Test the rear defog relay control circuit of the rear window defogger indicator 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 12  Go to Step 8 
7 Inspect for poor connections at the REAR DEFOG 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 12  Go to Step 10 
8 Inspect for poor connections at the harness connector of the BCM. 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 12  Go to Step 11 
9 Repair an open or high resistance in the rear defog relay control circuit of the REAR DEFOG relay. Refer to Wiring Repairs in Wiring Systems.
Did you complete the repair?		 Go to Step 12  -
10 Replace the REAR DEFOG relay. Refer to Relay Replacement (Within an Electrical Center) or Relay Replacement (Attached to Wire Harness) in Wiring Systems.
Did you complete the replacement?		 Go to Step 12  -
11
IMPORTANT: Perform the programming or setup procedure for the replaced control module if required.
Replace the BCM. Refer to Body Control Module Replacement in Body Control System for applicable replacement procedure.Did you complete the replacement?		 Go to Step 12  -
12
  1. Use the scan tool in order to clear the DTCs.
  2. Operate the vehicle within the Conditions for Setting the DTC as specified in the supporting text.
Does the DTC reset?		 Go to Step 2  System OK
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