Page 257 of 4284

FRONT IR SENSOR NOT CALIBRATED (STORED)
When Monitored: With the ignition on and the IOD fuse installed.
Set Condition: This DTC is set if the ATC cannot read the IR sensor values or the IR
sensor values are not within a defined range of the HVAC air door motor counts.
FRONT MODE DOOR NOT RESPONDING (STORED)
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.
FRONT MODE DOOR TRAVEL TOO LARGE (STORED)
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.
FRONT MODE DOOR TRAVEL TOO SMALL (STORED)
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.
PASS BLEND DOOR NOT RESPONDING (STORED)
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.
PASS BLEND DOOR TRAVEL TOO LARGE (STORED)
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.
PASS BLEND DOOR TRAVEL TOO SMALL (STORED)
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.
PCI BUS SHORTED HIGH (STORED)
When Monitored: With the ignition on.
Set Condition: This DTC is set if the ATC detects a short to voltage on the PCI Bus circuit.
PCI BUS SHORTED LOW (STORED)
When Monitored: With the ignition on.
Set Condition: This DTC is set if the ATC detects a short to ground on the PCI Bus circuit.
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Page 258 of 4284

REAR BLEND DOOR NOT RESPONDING (STORED)
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.
REAR BLEND DOOR RANGE TOO LARGE (STORED)
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.
REAR BLEND DOOR TRAVEL TOO SMALL (STORED)
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.
REAR FAN POT OPEN (STORED)
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 (STORED)
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 (STORED)
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 (STORED)
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 IR SENSOR NOT CALIBRATED (STORED)
When Monitored: With the ignition on and the IOD fuse installed.
Set Condition: This DTC is set if the ATC cannot read the IR sensor values or the IR
sensor values are not within a defined range of the HVAC air door motor counts.
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AC PRESSURE TOO HIGH (STORED) ÐContinued
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REAR MODE DOOR NOT RESPONDING (STORED)
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.
REAR MODE DOOR TRAVEL TOO LARGE (STORED)
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.
REAR MODE DOOR TRAVEL TOO SMALL (STORED)
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.
REAR MODE POT OPEN (STORED)
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 (STORED)
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.
RECIRC DOOR NOT RESPONDING (STORED)
When Monitored: Ignition in RUN and IOD fuse installed.
Set Condition: This DTC is set when the ATC does not receive feedback pulses within 5
seconds of the drive voltage being applied.
RECIRC DOOR TRAVEL TOO LARGE (STORED)
When Monitored: Ignition in RUN and 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.
RECIRC DOOR TRAVEL TOO SMALL (STORED)
When Monitored: Ignition in RUN and 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.
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AC PRESSURE TOO HIGH (STORED) ÐContinued
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POSSIBLE CAUSES
CHECK FOR ACTIVE ATC DTCS AND COOLDOWN TEST MESSAGES
STORED CODES TEST COMPLETE
TEST ACTION APPLICABILITY
1Note: Active codes must be resolved before diagnosing stored codes.
Anytime a code becomes active during this test, proceed to the conclusion question.
Turn the ignition on.
With the DRBIIIt, record and erase stored ATC DTC's.
Cycle the ignition switch.
Start the engine.
Monitor the DRBIIItfor active ATC DTCs while performing the following test steps.
Press the ATC Power switch on.
Turn the Front Blower switch to the low position.
Turn the Rear Blower switch to the Auto position.
Set the Driver, Rear, and Pass temperature controls to 60.
Turn the Mode switch to the panel position.
Press the Recirculation mode switch on, wait 30 seconds and then press it off.
Press the A/C mode switch on, wait 30 seconds and then press it off.
Press the Rear Defogger switch on, wait 30 seconds and then press it off.
Set the Driver temperature control to the max heat setting, wait 30 seconds and then
set it to the max cool setting. Repeat this step for the Rear and Pass temperature
controls.
Turn the Mode switch to each position for 30 seconds and then turn it back to the
panel position.
Turn the Front Blower switch to each position and then turn it back to the low
position.
Press the Auto HI switch, wait 30 seconds, press the Auto LO switch, wait 30 seconds
and then turn the Front Blower switch to the low position.
Turn the Rear Blower switch to each position and then turn it to the Rear Control
position.
On the Rear ATC Control, turn the Blower switch to each position and then turn it
to the low position.
On the Rear ATC Control, set the Rear temperature control to the max heat setting,
wait 30 seconds and then set it to the max cool setting.
On the Rear ATC Control, turn the Mode switch to each position for 30 seconds.
With the DRBIIIt, perform the ATC Cool Down test.
With the DRBIIIt, reset the ATC.
Place the vehicle on a hoist, and raise the wheels off the floor.
WARNING: Be sure to keep hands and feet clear of rotating wheels. Keep
clear of the engine's moving parts
Start engine. Place the transmission in drive. Brake off.
Does the DRBIIItdisplay any active ATC DTCs or Cooldown Test messages?All
Ye s®Return to the symptom list and choose the symptom(s)
Perform BODY VERIFICATION TEST - VER 1.
No®No problem found at this time.
Perform BODY VERIFICATION TEST - VER 1.
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AC PRESSURE TOO HIGH (STORED) ÐContinued
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Symptom:
COOLDOWN TEST FAILED
When Monitored and Set Condition:
COOLDOWN TEST FAILED
When Monitored: When executing the Cooldown Test.
Set Condition: This DTC is set if the A/C system is unable to bring the evaporator
temperature down 6.7ÉC (20ÉF) within two minutes.
POSSIBLE CAUSES
OTHER COOLDOWN TEST MESSAGES PRESENT
ATC DTC(S) PRESENT
CHECK THE PCM/ECM FOR DTCS
A/C SYSTEM TESTING
TEST ACTION APPLICABILITY
1NOTE: The work area ambient temperature must be above 10ÉC (50ÉF) to
test A/C system operation.
Are any other messages displayed with the Cooldown Test Failed message?All
Ye s®Return to the symptom list and choose the symptom(s).
After the repair is complete, rerun the Cooldown Test.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 2
2NOTE: The work area ambient temperature must be above 10ÉC (50ÉF) to
test A/C system operation.
Turn the ignition on.
With the DRBIIIt, read ATC DTCs.
Does the DRBIIItdisplay any ATC DTCs?All
Ye s®Return to the symptom list and choose the symptom(s).
After the repair is complete, rerun the Cooldown Test.
Perform BODY VERIFICATION TEST - VER 1.
No®Go To 3
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TEST ACTION APPLICABILITY
3NOTE: The work area ambient temperature must be above 10ÉC (50ÉF) to
test A/C system operation.
Turn the ignition on.
With the DRBIIIt, check the PCM/ECM for DTCs.
Are any PCM/ECM DTCs present?All
Ye s®Refer to Powertrain Diagnostic information for the related symp-
tom(s).
After the repair is complete, rerun the Cooldown Test.
Perform BODY VERIFICATION TEST - VER 1.
No®Refer to the Service Information for additional Cooldown Test
related diagnostic information and testing procedures.
After the repair is complete, rerun the Cooldown Test.
Perform BODY VERIFICATION TEST - VER 1.
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COOLDOWN TEST FAILED ÐContinued
Page 263 of 4284

Symptom:
DRIVER BLEND DOOR NOT RESPONDING (ACTIVE)
When Monitored and Set Condition:
DRIVER 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
DRIVER BLEND DOOR DRIVER CIRCUIT (A) SHORTED TO GROUND
DRIVER BLEND DOOR DRIVER CIRCUIT (B) SHORTED TO GROUND
DRIVER BLEND DOOR DRIVER CIRCUITS (A) AND (B) SHORTED TOGETHER
DRIVER BLEND DOOR DRIVER CIRCUIT (A) OPEN
DRIVER BLEND DOOR DRIVER CIRCUIT (B) OPEN
AT C
DRIVER BLEND DOOR ACTUATOR
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the Driver Blend Door Actuator harness connector.
Disconnect the ATC C1 harness connector.
Measure the resistance between ground and the Driver Blend Door Driver (A) circuit.
Is the resistance above 100k ohms?All
Ye s®Go To 2
No®Repair the Driver 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 Driver Blend Door Actuator harness connector.
Disconnect the ATC C1 harness connector.
Measure the resistance between ground and the Driver Blend Door Driver (B) circuit.
Is the resistance above 100k ohms?All
Ye s®Go To 3
No®Repair the Driver 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 Driver Blend Door Actuator harness connector.
Disconnect the ATC C1 harness connector.
Measure the resistance between the Driver Blend Door Driver (A) and (B) circuits.
Is the resistance above 100k ohms?All
Ye s®Go To 4
No®Repair the Driver 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 Driver Blend Door Actuator harness connector.
Disconnect the ATC C1 harness connector.
Measure the resistance of the Driver Blend Door Driver (A) circuit.
Is the resistance below 5.0 ohms?All
Ye s®Go To 5
No®Repair the Driver 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 Driver Blend Door Actuator harness connector.
Disconnect the ATC C1 harness connector.
Measure the resistance of the Driver Blend Door Driver (B) circuit.
Is the resistance below 5.0 ohms?All
Ye s®Go To 6
No®Repair the Driver 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 Driver 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 Driver Blend Door Actuator.
With the DRBIIIt, reset the ATC after repair/replacement is
complete.
Perform BODY VERIFICATION TEST - VER 1.
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DRIVER BLEND DOOR NOT RESPONDING (ACTIVE) ÐContinued