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For 1990-2009 cars only
Makes 🢒 Pontiac 🢒 2005 🢒 G6 🢒 Vehicle Control Systems 🢒 Vehicle DTC Information 🢒 DTC B0283

Circuit Description

The body control module (BCM) controls the rear window defogger relay circuit. When the ignition switch is in Run position and the operator has depressed the defogger switch, the BCM provides battery positive voltage to the rear window defogger relay control circuit. The rear window defogger relay coil is grounded to G302. If the rear window defogger relay positive control feed is shorted or if there is an open in the circuit, DTC B0283 will set.

DTC Descriptor

This diagnostic procedure supports the following DTC:

DTC B0283 Electric Rear Defrost Circuit

This vehicle has DTCs which include DTC Symptoms. For more information on DTC Symptoms, refer to in Vehicle DTC Information.

DTC Symptom

DTC Symptom Descriptor

02

Short to Ground

05

Short to Battery or Open

Conditions for Running the DTC

The system voltage must be between 9-16 volts.

Conditions for Setting the DTC
    • The BCM detects a short to ground in the rear window defogger relay control circuit when the BCM is trying to energize the relay.
    • The BCM detects a short to voltage in the rear window defogger relay control circuit when the BCM is trying to energize the relay.
    • The BCM detects that the rear window defogger relay control circuit is open.
    • The condition above must be present for more than 1 second.

Action Taken When the DTC Sets
    • The BCM stores DTC B0283 in memory.
    • The rear window defogger will not operate.

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 step tests for voltage at the coil side of the rear window defogger relay. The BATT MAIN 3 fuse supplies power to the coil side of the rear window defogger relay.

    2.

  2. This step tests the control circuit side of the rear window defogger relay for faults that cause both DTC B0283.

    3.

  3. Listen for an audible click when the rear window defogger relay operates. Command both the ON and OFF states. Repeat the commands as necessary.

    4.

  4. This step verifies that the BCM is providing ground to the rear window defogger relay.

    5.

  5. After replacement of the BCM, you must calibrate the new module for proper operation.

Step

Action

Yes

No

Schematic Reference: Defogger Schematics

Connector End View Reference: Stationary Windows Connector End Views

1

Did you perform the Diagnostic System Check - Vehicle?

Go to Step 2

Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2

  1. Remove the rear window defogger relay.
  2. Connect a test lamp between the rear window defogger relay ground feed circuit and a B+ at the rear window defogger relay socket. Refer to Circuit Testing in Wiring Systems.
  3. Turn ON the ignition, with the engine OFF.

Does the test lamp illuminate?

Go to Step 3

Go to Step 8

3

  1. Turn OFF the ignition.
  2. Test the body control module (BCM) controlled circuit of the rear window defogger relay for a short to voltage and ground as required by the schematic. Refer to Circuit Testing in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 4

4

  1. Connect a test lamp between the ground side of the control circuit and the BCM controlled circuit of the rear window defogger relay socket.
  2. Turn ON the ignition, with the engine OFF.
  3. Using a scan tool, command the relay ON then OFF.

Does the test lamp turn ON and OFF?

Go to Step 6

Go to Step 5

5

Test the control circuit of the rear window defogger relay for an open. Refer to Circuit Testing in Wiring Systems.

Did you find and correct the condition?

Go to Step 11

Go to Step 7

6

Inspect for poor connections and terminal damage at the relay socket. 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 11

Go to Step 9

7

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 11

Go to Step 10

8

Repair the ground side of the control circuit of the rear window defogger relay. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

Go to Step 11

--

9

Replace the rear window defogger relay.

Did you complete the replacement?

Go to Step 11

--

10

Replace the BCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup, and programming.

Did you complete the replacement?

Go to Step 11

--

11
  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