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For 1990-2009 cars only

Rear Window Defogger Inoperative CJ2

CJ2

Step

Action

Value(s)

Yes

No

1

Did you perform the Defogger Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Defogger

2

  1. Install a scan tool and go to the BCM Input Display Data 2 screen.
  2. Turn on the Rear Defog Switch.

Does the scan tool indicate the the Rear Defog Relay is Active?

--

Go to Step 4

Go to Step 3

3

  1. Go to BCM Output Controls.
  2. Attempt to activate the Rear Defog Relay with the scan tool.

Does the scan tool indicate the Rear Defog Relay is Active?

--

Go to Step 10

Go to Step 11

4

Inspect the RR DEFOG fuse #48.

Is the fuse open?

--

Go to Step 5

Go to Step 6

5

Repair circuit 293 for a short to ground.

Did you complete the repair?

--

Go to Step 12

--

6

Test and repair circuit 293 for an open or high resistance.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 7

7

Test and repair circuit 350 for an open or high resistance.

Did you find and correct the condition?

--

Go to Step 12

Go to Step 8

8

Test and repair the Rear Defogger Grid for any open conditions. Refer to Defogger Grid Lines Diagnosis and Grid Line Repair .

Did you find and correct the condition?

--

Go to Step 12

Go to Step 9

9

Replace the RR DEFOG Mini Relay #44.

Did you complete the replacement?

--

Go to Step 12

--

10

Replace the HVAC Control Assembly. Refer to Control Assembly Replacement .

Did you complete the replacement?

--

Go to Step 12

--

11

Replace the Body Control Module. Refer to Body Control Module Replacement and Body Control Module (BCM) Programming/RPO Configuration .

Did you complete the replacement?

--

Go to Step 12

--

12

  1. Clear any DTCs which may have set. Refer to Diagnostic Trouble Code (DTC) Clearing .
  2. Operate the system in order to verify the condition.

Did you correct the condition?

--

System OK

Go to Diagnostic System Check - Defogger

Rear Window Defogger Inoperative C60

C60

Step

Action

Value(s)

Yes

No

1

Did you perform the Defogger Diagnostic System Check?

--

Go to Step 2

Go to Diagnostic System Check - Defogger

2

  1. Install a scan tool and go to the BCM Input Display Data 2 screen.
  2. Turn on the Rear Defog Switch.

Does the scan tool indicate the the Rear Defog Relay is Active?

--

Go to Step 4

Go to Step 3

3

  1. Go to BCM Output Controls.
  2. Attempt to activate the Rear Defog Relay with the scan tool.

Does the scan tool indicate the Rear Defog Relay is Active?

--

Go to Step 10

Go to Step 12

4

Inspect the RR DEFOG fuse #48.

Is the fuse open?

--

Go to Step 5

Go to Step 6

5

Repair circuit 293 for a short to ground.

Did you complete the repair?

--

Go to Step 13

--

6

Test and repair circuit 293 for an open or high resistance.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 7

7

Test and repair circuit 350 for an open or high resistance.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 8

8

Test and repair the Rear Defogger Grid for any open conditions. Refer to Defogger Grid Lines Diagnosis and Grid Line Repair .

Did you find and correct the condition?

--

Go to Step 13

Go to Step 9

9

Replace the RR DEFOG Mini Relay #44.

Did you complete the replacement?

--

Go to Step 13

--

10

Test and repair circuit 681for an open or high resistance condition or a short to ground.

Did you find and correct the condition?

--

Go to Step 13

Go to Step 11

11

Replace the HVAC Control Assembly. Refer to Control Assembly Replacement .

Did you complete the replacement?

--

Go to Step 13

--

12

Replace the Body Control Module. Refer to Body Control Module Replacement and Body Control Module (BCM) Programming/RPO Configuration .

Did you complete the replacement?

--

Go to Step 13

--

13

  1. Clear any DTCs which may have set. Refer to Diagnostic Trouble Code (DTC) Clearing .
  2. Operate the system in order to verify the condition.

Did you correct the condition?

--

System OK

Go to Diagnostic System Check - Defogger