Diagnostic Aids

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A dead zone exists in a range 10 counts above or below the mode door max or mode door min positions. When the mode door actual data parameter is within the dead zone, the DTC will not set. If the mode door commanded data parameter differs from the mode door actual data parameter by 4 counts or more outside the dead zone, the DTC will set.
A damaged or broken mode door and or actuator can cause this DTC to set.

DTC B0248

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 Commanded data parameter and the Mode Door Actual data parameter in the Primary ECC Data list. Does the scan tool indicate that the Mode Door Commanded data parameter is within the specified value of the Mode Door Actual data parameter?	0-3 counts	Go to TESTING FOR INTERMITTENT AND POOR CONNECTIONS	Go to Step 3
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 ignition 3 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 an open. 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 control 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 test. Turn on the ignition, with the engine off. With the scan tool, observe mode actuator actual parameter in the Primary ECC Data List. Connect a 3-amp fused jumper wire between the mode door control circuit of the mode actuator and the 5-volt reference circuit of the mode actuator This action drives the door to panel. Remove the reconnect the jumper wire between the mode door control circuit of the mode actuator to ground circuit of the mode actuator this action drives the door to defrost. Does the mode actuator drive shaft rotate and do the counts change?	-	Go to Step 13	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 door from operating within it's full range of motion. Did you find and correct the condition?	-	Go to Step 10	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