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 limiting travel. An actual range above this limit suggests an over travel condition, damaged or missing foam seals.
A damaged or broken auxiliary air temperature door and or actuator can cause this DTC to set.
If condition not present refer to TESTING FOR INTERMITTENT AND POOR CONNECTIONS .

DTC B0434

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 Aux. Mix Door Max Position data parameter and the Aux. Mix Door Min Position data parameter in the Auxiliary ECC Data list. Subtract the Aux. Mix Door Min Position from the Aux. Mix Door Max Position. Does the result of the calculation indicate that the actual travel of the auxiliary air temperature actuator is within the specified range?	64-216 Counts	Go to Step 3	Go to Step 8
3	With the scan tool, command the auxiliary air temperature actuator from HOT to COLD. With the scan tool, observe the Aux. Mix Door Actual data parameter in the Auxiliary ECC data list. Does the scan tool indicate that the Aux. Mix Door Actual data parameter is within the specified range?	5-250 Counts	Go to TESTING FOR INTERMITTENT AND POOR CONNECTIONS	Go to Step 4
4	Test the ground circuit of the auxiliary air temperature actuator 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 auxiliary air temperature actuator for a 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 6
6	Test the signal circuit of the auxiliary air temperature actuator for an open, high resistance, 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 auxiliary air temperature actuator connector and the auxiliary HVAC control module connector must be connected to correctly perform test. Turn ON the ignition, with the engine OFF. With the scan tool, observe the Aux. Mix Door Actual data parameter in the Auxiliary ECC Data list. Connect a 3 amp fused jumper wire between the control circuit and the 5 volt reference circuit of the auxiliary air temperature actuator. This drives the actuator to the full cold position. Remove and reconnect the jumper wire between the control circuit and the ground circuit of the auxiliary air temperature actuator. This drives the actuator to the full hot position. Does the auxiliary air temperature actuator drive shaft rotate and do the counts change?	-	Go to Step 10	Go to Step 9
8	Inspect the auxiliary air temperature door and the auxiliary air temperature actuator for the following: Incorrectly installed auxiliary air temperature actuator. Broken or binding linkages or auxiliary air temperature door. Obstruction that prevents the auxiliary air temperature door from operating within it's full range of motion. Did you find and correct the condition?	-	Go to Step 13	Go to Diagnostic Aids
9	Inspect for poor connections at the harness connector of the auxiliary air temperature 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 auxiliary 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	Replace the auxiliary air temperature actuator. Refer to AIR TEMPERATURE ACTUATORS - AUXILIARY . Did you complete the replacement?	-	Go to Step 13	-
12	Replace the auxiliary HVAC control module. Refer to HVAC Control Module Replacement - Auxiliary . 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