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.
228
AUTOMATIC TEMPERATURE CONTROL
AC PRESSURE TOO HIGH (STORED) ÐContinued
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.
230
AUTOMATIC TEMPERATURE CONTROL
AC PRESSURE TOO HIGH (STORED) ÐContinued
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.
231
AUTOMATIC TEMPERATURE CONTROL
AC PRESSURE TOO HIGH (STORED) ÐContinued
Symptom:
FRONT MODE DOOR NOT RESPONDING (ACTIVE)
When Monitored and Set Condition:
FRONT MODE 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
MODE DOOR DRIVER CIRCUIT (A) SHORTED TO GROUND
MODE DOOR DRIVER CIRCUIT (B) SHORTED TO GROUND
MODE DOOR DRIVER CIRCUITS (A) AND (B) SHORTED TOGETHER
MODE DOOR DRIVER CIRCUIT (A) OPEN
MODE DOOR DRIVER CIRCUIT (B) OPEN
AT C
MODE DOOR ACTUATOR
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the Mode Door Actuator harness connector.
Disconnect the ATC C1 harness connector.
Measure the resistance between ground and the Mode Door Driver (A) circuit.
Is the resistance above 100k ohms?All
Ye s®Go To 2
No®Repair the Mode 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 Mode Door Actuator harness connector.
Disconnect the ATC C1 harness connector.
Measure the resistance between ground and the Mode Door Driver (B) circuit.
Is the resistance above 100k ohms?All
Ye s®Go To 3
No®Repair the Mode 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.
252
AUTOMATIC TEMPERATURE CONTROL
Symptom:
FRONT MODE DOOR TRAVEL TOO SMALL (ACTIVE)
When Monitored and Set Condition:
FRONT MODE 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 MODE DOOR
MODE DOOR ACTUATOR
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRB, read the active ATC DTCs.
Is the FRONT MODE 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 Mode Door Actuator harness connector.
Connect a 12-volt Test Light between the Mode Door Actuator harness connector
cavities.
Turn the ignition on.
While monitoring the test light, turn the mode control knob in each position.
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.
256
AUTOMATIC TEMPERATURE CONTROL
Symptom:
REAR MODE DOOR NOT RESPONDING (ACTIVE)
When Monitored and Set Condition:
REAR MODE 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 MODE DOOR DRIVER CIRCUIT (A) SHORTED TO GROUND
REAR MODE DOOR DRIVER CIRCUIT (B) SHORTED TO GROUND
REAR MODE DOOR DRIVER CIRCUITS (A) AND (B) SHORTED TOGETHER
REAR MODE DOOR DRIVER CIRCUIT (A) OPEN
REAR MODE DOOR DRIVER CIRCUIT (B) OPEN
AT C
REAR MODE DOOR ACTUATOR
TEST ACTION APPLICABILITY
1 Turn the ignition off.
Disconnect the ATC C1 harness connector.
Measure the resistance between ground and the Rear Mode Door Driver (A) circuit.
Is the resistance above 100k ohms?All
Ye s®Go To 2
No®Repair the Rear Mode 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 ATC C1 harness connector.
Measure the resistance between ground and the Rear Mode Door Driver (B) circuit.
Is the resistance above 100k ohms?All
Ye s®Go To 3
No®Repair the Rear Mode 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.
284
AUTOMATIC TEMPERATURE CONTROL
Symptom:
REAR MODE DOOR TRAVEL TOO SMALL (ACTIVE)
When Monitored and Set Condition:
REAR MODE 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 MODE DOOR
REAR MODE DOOR ACTUATOR
TEST ACTION APPLICABILITY
1 Turn the ignition on.
With the DRB, read the active ATC DTCs.
Is the REAR MODE 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 Mode Door Actuator harness connector.
Connect a 12-volt Test Light between the rear mode door driver (A) and (B) circuits
in the Rear A/C Heater Unit harness connector.
Turn the ignition on.
While monitoring the test light, turn the rear mode 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.
288
AUTOMATIC TEMPERATURE CONTROL
TEST ACTION APPLICABILITY
2WARNING: DO NOT OPERATE THE DCHA IN AN ENCLOSED AREA SUCH
AS A GARAGE THAT DOES NOT HAVE EXHAUST VENTILATION FACILI-
TIES. ALWAYS VENT THE DCHA's EXHAUST WHEN OPERATING THE
DCHA. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN
PERSONAL INJURY OR DEATH.
Turn the ignition on.
With the DRBIIIt, read Cabin Heater DTCs.
Is DTC B1813 Heater In Lockout Mode present?All
Ye s®Go To 3
No®Go To 4
3WARNING: DO NOT OPERATE THE DCHA IN AN ENCLOSED AREA SUCH
AS A GARAGE THAT DOES NOT HAVE EXHAUST VENTILATION FACILI-
TIES. ALWAYS VENT THE DCHA's EXHAUST WHEN OPERATING THE
DCHA. FAILURE TO FOLLOW THESE INSTRUCTIONS MAY RESULT IN
PERSONAL INJURY OR DEATH.
Start the engine.
Allow the engine to idle.
Turn the A/C - Heater Control Module's Power switch on.
Turn the Blower switch to the high speed position.
Set the Blend Control to the max heat position.
Remove Cabin Heater Fuse #15 from the IPM for a minimum of five seconds, then
reinstall the fuse. The DCHA may attempt to start.
Turn the Blower switch off and turn the A/C - Heater Control Module's Power switch
off.
Turn the engine off.
View repairAll
Repair
Go To 4
297
CABIN HEATER
CABIN HEATER PRE-TEST ÐContinued