Diagnostic Aids

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The range fault can only be detected following a recalibration. The recalibration can only be initiated by removing the battery positive voltage circuit to the HVAC control module.
The calibration limit is 64-216 counts. An actual range below this limit suggests an obstruction, something stuck in the door which limits travel. An actual range above this limit suggests an excessive travel condition, damaged, or missing foam seals.
A damaged mode door or a damaged actuator can cause this DTC to set.
An intermittent short to ground on the HVAC class 2 serial data circuit can set this DTC. Recalibrate actuators and test system.
If the condition is not present, refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS .

DTC B3761

Step	Action	Values	Yes	No
Schematic Reference: HVAC Schematics
1	Did you perform the HVAC Diagnostic System Check?	-	Go to Step 2	Go to Diagnostic System Check - HVAC Systems - Automatic
2	Install the scan tool. Turn ON the ignition, with the engine OFF. With the scan tool, observe the mode door max. position data parameter and the mode door min. position data parameter in the Primary ECC Data List Subtract the mode door min. position from the mode door max. position. Does the result of the calculation indicate that the actual travel of the mode actuator is within the specified range?	64-216 counts	Go to Step 3	Go to Step 8
3	With the scan tool, command the mode actuator from panel (ON) to defrost (OFF). With the scan tool, observe the mode actuator actual position. Does the scan tool indicate that the mode actuator actual parameter changes within the specified range when it is commanded from panel to defrost?	5-250 counts	Go to Diagnostic Aids	Go to Step 4
4	Test the mode door actuator ground circuit for an open. Refer to CIRCUIT TESTING and WIRING REPAIRS . Did you find and correct the condition?	-	Go to Step 13	Go to Step 5
5	Test the 5 volt reference circuit of the mode actuator for a short to ground. Refer to CIRCUIT TESTING and WIRING REPAIRS . Did you find and correct the condition?	-	Go to Step 13	Go to Step 6
6	Test the mode door position signal circuit for an open, short to ground or short to voltage. Refer to CIRCUIT TESTING and WIRING REPAIRS . Did you find and correct the condition?	-	Go to Step 13	Go to Step 7
7	IMPORTANT: The mode actuator connector and the HVAC control module connector must be connected to correctly perform this test. Turn on the ignition, with the engine off. With the scan tool, observe the mode actuator actual parameter in the Primary ECC Data List. Connect a 3 amp fused jumper wire between the mode door motor control circuit of the mode actuator and the 5 volt reference circuit of the mode actuator (drives the door to panel). Remove and reconnect the jumper wire between the mode door control circuit of the mode actuator to the ground circuit of the mode actuator (drives the door to defrost). Does the drive shaft of the mode actuator rotate and do the counts change?	-	Go to Step 10	Go to Step 8
8	Inspect the mode door and the mode actuator for the following. Incorrectly installed mode actuator. Broken or binding linkages or mode door. Obstruction that prevents the mode actuator from operating within it's full range of motion. Did you find and correct the condition?	-	Go to Step 13	Go to Step 9
9	Inspect for poor connections at the harness connector of the mode actuator. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS and CONNECTOR REPAIRS . Did you find and correct the condition?	-	Go to Step 13	Go to Step 11
10	Inspect for poor connections at the harness connector of the HVAC control module. Refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS and CONNECTOR REPAIRS . Did you find and correct the condition?	-	Go to Step 13	Go to Step 12
11	IMPORTANT: Perform the recalibration procedure for the mode actuator. Replace the mode actuator. Refer to Mode Actuator Replacement (W/ D07) or Mode Actuator Replacement (W/O D07) .Did you complete the replacement?	-	Go to Step 13	-
12	IMPORTANT: Perform the recalibration procedure for the HVAC control module. Replace the HVAC control module. Refer to HVAC Control Module Replacement .Did you complete the replacement?	-	Go to Step 13	-
13	Use the scan tool in order to clear the DTCs. Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text. Does the DTC reset?	-	Go to Step 2	System OK