Did you review the HVAC operation and perform the necessary inspections?

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Go to Step 2

Go to Symptoms - HVAC Systems - Manual

1. Turn the ignition switch to the RUN position.
2. Use the J 39200 Digital Multimeter (DMM) in order to measure the voltage between terminal C of the heater A/C control assembly connector C2 and ground.

Does the voltage measured equal the specified value?

B+

Go to Step 3

Go to Step 4

1. Disconnect the heater A/C control assembly connector C2.
2. Use the J 39200 DMM in order to measure the voltage between terminal C and terminal K of the heater A/C control assembly connector C2.

Does the voltage measured equal the specified value?

B+

Go to Step 5

Go to Step 6

Use the J 39200 DMM in order to measure the voltage between terminal A11 of the underhood wiring harness junction block connector C3 and ground.

Does the voltage measured equal the specified value?

B+

Go to Step 7

Go to Step 8

1. Reconnect the heater A/C control assembly connector C2.
2. Use the J 39200 DMM in order to backprobe the heater A/C control assembly connector C2.
3. Measure the voltage between terminal G and ground.
4. Turn the temperature control from COLD to HOT.

Does the voltage vary within the specified range?

1-12 V

Go to Step 9

Go to Step 10

Repair the open in CKT 251 between the heater A/C control assembly and ground splice pack G204. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

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System OK

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Repair the open in CKT 41 between the underhood wiring harness junction block and the heater A/C control assembly. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

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System OK

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Replace the underhood wiring harness junction block. Refer to Underhood Fuse Block Replacement in Engine Electrical.

Is the repair complete?

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System OK

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1. Disconnect the air temperature actuator connector.
2. Connect the J 39200 DMM between terminal 8 of the air temperature actuator connector and ground.
3. Turn the temperature control from COLD to HOT.

Does the voltage vary within the specified range?

1-12 V

Go to Step 11

Go to Step 12

Replace the heater A/C control assembly. Refer to LINK Control Assembly Replacement .

Is the repair complete?

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System OK

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Connect the J 39200 DMM between terminal 10 of the air temperature actuator connector and ground.

Does the voltage measured equal the specified value?

B+

Go to Step 13

Go to Step 14

Repair the open in CKT 733 between the air temperature actuator and the heater A/C control assembly. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

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System OK

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Use the J 39200 DMM in order to measure the voltage between terminal 7 and terminal 10 of the air temperature actuator connector.

Does the voltage measured equal the specified value?

B+

Go to Step 15

Go to Step 16

Repair the open in CKT 41 between the underhood wiring harness junction block and the air temperature actuator. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

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System OK

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Replace the air temperature actuator. Refer to LINK Temperature Actuator Replacement .

Is the repair complete?

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System OK

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Repair the open in CKT 251 between the air temperature actuator and ground splice pack G204. Refer to Wiring Repairs in Wiring Systems.

Is the repair complete?

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System OK

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