Circuit / System Verification

NOTE:

Ambient temperature MUST BE below 7°C (45°F) in order to complete the following verification procedure.

Vehicle Power Mode - In Propulsion / Run Mode.
Verify the scan tool parameter: Ambient Air Temperature = -40 to 88°C (-40 to 190°F) and changes.
- If not the specified state
  Refer to: Outside Air Temperature Display Malfunction
- Go to next step: If the specified state
Operate the component: Rear window defogger switch through the A26 Heater and Air Conditioning User Interface Control - Front - Selected ON.
Verify the component turns On and Off: E18 Rear Window Defogger Grid.
- If the component does not turn On and Off
  Refer to: Rear Window Defogger Malfunction
- Go to next step: If the component turns On and Off
E18 Rear Window Defogger Grid = Active & Ambient Air Temperature < 7°C (45°F).
Verify the component is active: E49 Windshield Heating Grid.
- If not the specified state
  Refer to: Circuit / System Testing
- Go to next step: If the specified state
E18 Rear Window Defogger Grid = Off.
Verify the component is not active: E49 Windshield Heating Grid.
- If not the specified state
  Refer to: Circuit / System Testing
- Go to next step: If the specified state
A fault is not currently present and may be an intermittent condition