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Symptom:
REAR BLEND DOOR NOT RESPONDING (ACTIVE)
When Monitored and Set Condition:
REAR BLEND DOOR NOT RESPONDING (ACTIVE)
When Monitored: With the ignition on and the IOD fuse installed.
Set Condition: This DTC is set if the ATC does not receive feedback pulses within 5
seconds of the drive voltage being applied.
POSSIBLE CAUSES
REAR BLEND DOOR DRIVER CIRCUIT (A) SHORTED TO GROUND
REAR BLEND DOOR DRIVER CIRCUIT (B) SHORTED TO GROUND
REAR BLEND DOOR DRIVER CIRCUITS (A) AND (B) SHORTED TOGETHER
REAR BLEND DOOR DRIVER CIRCUIT (A) OPEN
REAR BLEND DOOR DRIVER CIRCUIT (B) OPEN
AT C
REAR BLEND DOOR ACTUATOR
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the Rear Blend Door Actuator harness connector.
Disconnect the ATC C1 harness connector.
Measure the resistance between ground and the Rear Blend Door Driver (A) circuit.
Is the resistance above 100k ohms?All
Ye s®Go To 2
No®Repair the Rear Blend Door Driver (A) circuit for a short to
ground.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
2 Turn the ignition off.
Disconnect the Rear Blend Door Actuator harness connector.
Disconnect the ATC C1 harness connector.
Measure the resistance between ground and the Rear Blend Door Driver (B) circuit.
Is the resistance above 100k ohms?All
Ye s®Go To 3
No®Repair the Rear Blend Door Driver (B) circuit for a short to
ground.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
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TEST ACTION APPLICABILITY
3 Turn the ignition off.
Disconnect the Rear Blend Door Actuator harness connector.
Disconnect the ATC C1 harness connectors.
Measure the resistance between the Rear Blend Door Driver (A) and (B) circuits.
Is the resistance above 100k ohms?All
Ye s®Go To 4
No®Repair the Rear Blend Door Driver (A) and (B) circuits for a short
together.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
4 Turn the ignition off.
Disconnect the Rear Blend Door Actuator harness connector.
Disconnect the ATC C1 harness connector.
Measure the resistance of the Rear Blend Door Driver (A) circuit.
Is the resistance below 5.0 ohms?All
Ye s®Go To 5
No®Repair the Rear Blend Door Driver (A) circuit for an open.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
5 Turn the ignition off.
Disconnect the Rear Blend Door Actuator harness connector.
Disconnect the ATC C1 harness connector.
Measure the resistance of the Rear Blend Door Driver (B) circuit.
Is the resistance below 5.0 ohms?All
Ye s®Go To 6
No®Repair the Rear Blend Door Driver (B) circuit for an open.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
6 Turn the ignition off.
Disconnect the ATC C1 harness connector.
Measure the resistance between the Rear Blend Door Driver (A) and (B) circuits.
Is the resistance between 26.0 and 46.0 ohms?All
Ye s®Replace the ATC.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 7
7 If there are no possible causes remaining, view repair. All
Repair
Replace the Rear Blend Door Actuator.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
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REAR BLEND DOOR NOT RESPONDING (ACTIVE) ÐContinued
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Symptom:
REAR BLEND DOOR TRAVEL TOO LARGE (ACTIVE)
When Monitored and Set Condition:
REAR BLEND DOOR TRAVEL TOO LARGE (ACTIVE)
When Monitored: With the ignition on and the IOD fuse installed.
Set Condition: This DTC is set when the ATC monitors the travel range during system
initialization and the measured range is greater than expected.
POSSIBLE CAUSES
CHECK THE ATC FOR DTCS
REAR BLEND DOOR ACTUATOR
REAR BLEND DOOR LINKAGE
AT C
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRB, read the active ATC DTC's.
Is the REAR BLEND DOOR NOT RESPONDING DTC set?All
Ye s®Return to the symptom list and choose the symptom.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 2
2 Turn the ignition off.
Remove the Rear Blend Door Actuator.
By hand, attempt to rotate the Rear Blend Door Actuator in both directions.
Did the blend door actuator turn in either direction?All
Ye s®Replace the Rear Blend Door Actuator.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 3
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TEST ACTION APPLICABILITY
3 Remove the Rear Blend Door Actuator. Rotate the blend door (door only). Note: This
should rotate approximately 45 degrees from stop to stop.
Inspect the blend door linkage for excessive wear or missing linkage.
Were any mechanical problems found?All
Ye s®Repair or replace the rear blend door/linkage as necessary.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
No®Replace the ATC.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
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REAR BLEND DOOR TRAVEL TOO LARGE (ACTIVE) ÐContinued
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Symptom:
REAR BLEND DOOR TRAVEL TOO SMALL (ACTIVE)
When Monitored and Set Condition:
REAR BLEND DOOR TRAVEL TOO SMALL (ACTIVE)
When Monitored: With the ignition on and the IOD fuse installed.
Set Condition: This DTC is set when the ATC monitors the travel range during system
initialization and the measured range is less than expected.
POSSIBLE CAUSES
CHECK THE ATC FOR DTCS
AT C
OBSTRUCTED BLEND DOOR
REAR BLEND DOOR ACTUATOR
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRB, read the active ATC DTCs.
Is the REAR BLEND DOOR NOT RESPONDING DTC set?All
Ye s®Return to the symptom list and choose the symptom.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 2
2 Turn the ignition off.
Disconnect the Rear Blend Door Actuator harness connector.
Connect a 12-volt Test Light across the Rear Blend Door Actuator harness connector.
Turn the ignition on.
While monitoring the test light, turn the rear blend control knob from lo to hi.
Note: Observe test light for approximately 30 seconds.
Does the test light start to flash and stay flashing?All
Ye s®Go To 3
No®Replace the ATC.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
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TEST ACTION APPLICABILITY
3 Remove the Rear Blend Door Actuator. Rotate the blend door (door only). Note: This
should rotate approximately 45 degrees from stop to stop.
Does the rear blend door move smoothly in both directions?All
Ye s®Replace the Rear Blend Door Actuator.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
No®Repair or replace the blend door as necessary.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
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REAR BLEND DOOR TRAVEL TOO SMALL (ACTIVE) ÐContinued
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Symptom List:
REAR FAN POT OPEN (ACTIVE)
REAR FAN POT SHORTED (ACTIVE)
REAR IR SENSOR HIGH (ACTIVE)
REAR IR SENSOR LOW (ACTIVE)
REAR MODE POT OPEN (ACTIVE)
REAR MODE POT SHORTED (ACTIVE)
Test Note: All symptoms listed above are diagnosed using the same tests.
The title for the tests will be REAR FAN POT OPEN (ACTIVE).
When Monitored and Set Condition:
REAR FAN POT OPEN (ACTIVE)
When Monitored: With the ignition on and the IOD fuse installed.
Set Condition: This DTC is set if the ATC reads the rear blower switch value and it is
above 250 A/D counts.
REAR FAN POT SHORTED (ACTIVE)
When Monitored: With the ignition on and the IOD fuse installed.
Set Condition: This DTC is set if the ATC reads the rear fan switch value and it is below
5 A/D counts.
REAR IR SENSOR HIGH (ACTIVE)
When Monitored: With the ignition on and the IOD fuse installed.
Set Condition: This DTC is set if the ATC reads the Rear IR Sensor value and it is above
250 A/D counts.
REAR IR SENSOR LOW (ACTIVE)
When Monitored: With the ignition on and the IOD fuse installed.
Set Condition: This DTC is set if the ATC reads the Rear IR Sensor value and it is below
5 A/D counts.
REAR MODE POT OPEN (ACTIVE)
When Monitored: With the ignition on and the IOD fuse installed.
Set Condition: This DTC is set if the ATC reads the rear mode select switch value and it
is above 250 A/D counts.
REAR MODE POT SHORTED (ACTIVE)
When Monitored: With the ignition on and the IOD fuse installed.
Set Condition: This DTC is set if the ATC reads the rear mode select switch value and it
is below 5 A/D counts.
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POSSIBLE CAUSES
REAR ATC SWITCH
TEST ACTION APPLICABILITY
1 This DTC indicates a fault in the Rear ATC Switch.
View repair.All
Repair
Replace the Rear ATC Switch.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
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REAR FAN POT OPEN (ACTIVE) ÐContinued