The number(s) below refer to the step number(s) on the diagnostic table.
The specified values are from the A/C System Performance Test.
The voltage will vary between 0-12 volts during normal operation. The HVAC control module connector must be connected during this step.
Step | Action | Value(s) | Yes | No | ||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Schematic Reference: HVAC Schematics Connector End View Reference: HVAC Connector End Views DEFINITION: The temperature can not be adjusted, or the cooling is insufficient during A/C operation. | ||||||||||||||
1 | Did you perform the HVAC Diagnostic System Check? | -- | Go to Step 2 | |||||||||||
2 |
Does the blower motor operate at all? | -- | Go to Step 3 | Go to Blower Motor Inoperative | ||||||||||
3 | Does the blower motor operate in each of the speed positions? | -- | Go to Step 4 | Go to Blower Motor Malfunction | ||||||||||
4 | Alternately place the Recirculation Door between MAX A/C and Vent. Does the Recirculation Door operate move from the recirculation position to the outside air position? | -- | Go to Step 5 | Go to Air Delivery Improper | ||||||||||
5 | Does the Too Hot in Vehicle concern occur when A/C cooling is desired? | -- | Go to Step 6 | Go to Step 8 | ||||||||||
6 |
IMPORTANT:: For A/C compressor operation, ambient air temperature must be above 3°C (38°F).
Does the A/C compressor clutch engage? | -- | Go to Step 7 | |||||||||||
Perform the A/C system performance test. Refer to Air Conditioning (A/C) System Performance Test in Heating, Ventilation and Air Conditioning. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 8 | |||||||||||
8 |
Does the drive shaft of the air temperature actuator rotate? | -- | Go to Step 9 | Go to Step 10 | ||||||||||
9 | Inspect the air temperature door and the air temperature actuator for the following conditions:
Did you find and correct the condition? | -- | Go to Step 19 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | ||||||||||
10 | Test the ignition 3 voltage circuit of the air temperature actuator for an open or a high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 11 | ||||||||||
11 | Test the ground circuit of the air temperature actuator for an open or high resistance. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 12 | ||||||||||
12 | Test the air temperature door control circuit of the air temperature actuator for an open, high resistance, short to ground, or short to voltage. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 13 | ||||||||||
Important: Ensure that the HVAC control assembly connector is connected during this step to avoid misdiagnosis.
Does the voltage measure within the specified values with a smooth transition between Cold and Hot? | 12 V at Cold 0 V at Hot | Go to Step 14 | Go to Step 16 | |||||||||||
14 | Inspect for poor connections at the harness connector of the air temperature actuator. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 15 | ||||||||||
15 | Inspect the air temperature actuator, door and any attaching linkage for binding or a condition that prevents drive shaft rotation. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 17 | ||||||||||
16 | Inspect for poor connections at the harness connector of the HVAC control assembly. Refer to Testing for Intermittent Conditions and Poor Connections and Connector Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 19 | Go to Step 18 | ||||||||||
17 | Replace the air temperature actuator. Refer to Air Temperature Actuator Replacement . Did you complete the replacement? | -- | Go to Step 19 | -- | ||||||||||
18 | Replace the HVAC control assembly. Refer to Heater and Air Conditioning Control Replacement . Did you complete the replacement? | -- | Go to Step 19 | -- | ||||||||||
19 | Operate the system in order to verify the repair. Did you correct the condition? | -- | System OK | Go to Step 2 |