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Automatic Temperature Control






B1044-Panel Mode Door 1 Travel Range Too Small

For a complete wiring diagram, refer to.

After the initial installation of the A/C Heater Control, the controller is calibrated to each individual blend/mode door actuator. These calibrations are stored as in the number of pulses it takes to move the door from one stop to another. The A/C Heater Control drives the Door Actuators by the use of Door Driver circuit and a Common Door Driver circuit and monitors all door actuator pulses to detect door movement in both directions. Most of the door actuators share a common door driver circuit but each door actuator has its own unique driver circuit. Due to shared circuitry, similar Diagnostic Trouble Codes (DTCs) can set at the same time for multiple actuators depending upon the type of circuit malfunction, its location, and the direction the actuator is moving when the malfunction is present.

When Monitored: Continuously when a door moment is commanded or when ever an Actuator Calibration Test is performed.

Set Condition: The A/C Heater Control uses a pulse feedback to the controller to detect the total door movement range. If the amount of pulses required to move the door completely in both directions is less than what the controller has stored in its memory, this DTC will set. If an Actuator Calibration Test is performed and the A/C Heater Control detects a valid range of the door movement span in both directions, the DTC will change from Active to Stored and will stay in the controllers memory for 100 ignition cycles.






Always perform the HVAC Pre-Diagnostic Troubleshooting procedure before proceeding. Refer to => Non-DTC Based
Diagnostics. HVAC Pre-Diagnostic Troubleshooting Procedure

Test Step 1 - CHECK FOR RELATED DTCS

Ignition on, engine not running.

Using the scan tool, read HVAC DTCs.

Is the DTC B1040-Panel Mode Door 1 Control Circuit/Performance also present?

Yes

Refer to => [ B1040-Panel Mode Door 1 Control Circuit/Performance ] B1040.

No

Go to Test Step 2 => [ Test Step 2 - CHECK IF DTC IS ACTIVE ]

Test Step 2 - CHECK IF DTC IS ACTIVE

Ignition on, engine not running.

Using the scan tool, read HVAC DTCs.

Is this DTC active?

Yes

Go to Test Step 4 => [ Test Step 4 - CHECK THE MODE DOOR ]

No

Go to Test Step 3 => [ Test Step 3 - PERFORM HVAC ACTUATOR CALIBRATION TEST ]

Test Step 3 - PERFORM HVAC ACTUATOR CALIBRATION TEST

Using the scan tool, perform the HVAC Actuator Calibration Test.

Did this DTC change from Stored to Active while performing the HVAC Actuator Calibration Test?

Yes

Go to Test Step 4 => [ Test Step 4 - CHECK THE MODE DOOR ]

No

Go to Test Step 6 => [ Test Step 6 - CHECK THE WIRING AND CONNECTORS ]

Test Step 4 - CHECK THE MODE DOOR

Remove the Mode Door Actuator and check the Mode Door for binding and full travel.

Were there any problems found?

Yes

Repair or replace the Mode Door as necessary.

Perform the HVAC Verification Test. Refer to => Non-DTC Based Diagnostics. HVAC Verification Test

No

Go to Test Step 5 => [ Test Step 5 - CHECK THE MODE DOOR ACTUATOR ]

Test Step 5 - CHECK THE MODE DOOR ACTUATOR

Replace the Mode Door Actuator.

Using the scan tool, erase HVAC DTCs.

Using the scan tool, perform the HVAC Actuator Calibration Test.

Did this DTC reset during HVAC Actuator Calibration Test?

Yes

Replace and program the A/C Heater Control.

Perform the HVAC Verification Test. Refer to => Non-DTC Based Diagnostics. HVAC Verification Test

No

Test complete.

Test Step 6 - CHECK THE WIRING AND CONNECTORS

The conditions necessary to set the DTC are not present at this time.

Using the scan tool, check the Environmental Data to help identify the conditions in which the DTC was set.

Using the wiring diagrams as a guide, check all related splices and connectors for signs of water intrusion, corrosion, pushed out or bent terminals, and correct pin tension.

Wiggle the wiring and connectors while checking for shorted and open circuits.

Were there any problems found?

Yes

Repair as necessary.

Perform the HVAC Verification Test. Refer to => Non-DTC Based Diagnostics. HVAC Verification Test

No

Test complete.