For 1990-2009 cars

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---
1 |

1. Turn the ignition switch to the ON position.
2. Press the rear window defogger switch ON. When the switch is pressed, the indicator turns ON.
3. After the switch is pressed, the rear window and outside rear view mirrors begin to warm up and defrost.

Does the rear window and outside rear view mirrors warm up and defrost when the rear window defogger switch is pressed?

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Go to Step 3

Go to Step 2

2 |

1. If the rear window defogger and both of the outside rear view mirrors are inoperative, refer to Rear Window Defogger Inoperative .
2. If the rear window defogger is inoperative, refer to Rear Window Defogger Inoperative .

Is the repair procedures complete?

--

System OK

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3 |

1. The procedure for reading DTCs is to use the scan tool.
2. When reading DTCs, follow the instructions that are supplied by the scan tool manufacturer.
3. Connect the scan tool.
4. Attempt to establish communication with the heater and A/C control.

Does the scan tool communicate with the heater and A/C control?

--

Go to Step 5

Go to Step 4

4 | Refer to Scan Tool Does Not Comm. with Heater and A/C Ctrl in Data Link Communications. Was the problem found and repaired? | -- | Go to Step 5 | --
5 | Are any current DTCs set? | -- | Go to Step 6 | Go to Step 7
6 |

• | If DTC 32 - Rear Window Defogger Signal Voltage Low is present, refer to DTC 32 Rear Window Defog Signal Voltage Low for diagnosis.

• | If DTC 33 - Rear Window Defogger Signal Voltage High or Open Circuit is present, refer to DTC 33 Rear Window Defog Signal Voltage Open CKT for diagnosis.

• | If DTC 34 - Rear Window Defogger Open Circuit is present, refer to DTC 34 Rear Window Defogger Open Circuit for diagnosis.

Is the repair procedures complete?

--

System OK

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7 | Are any history and/or intermittents DTCs displayed? | -- | Go to Step 8 | System OK
8 |

1. Locate the intermittent problem.
2. Repair the intermittent problem.

Was a problem found and repaired?

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System OK

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