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This PI Being Updated To Add Additional Model Years. Please Discard PI02080.
The following diagnosis might be helpful if the vehicle exhibits the symptom(s) described in this PI.
A replacement HVAC actuators is inoperative or that has worked one time and quit. The HVAC control head learns the stopping points based on how far the HVAC DOOR travels. If the actuator reachs the mechanical stops on the back of the actuator it will be outside of the range that the HVAC control head can learn. If the actuator was not mounted to the HVAC case prior to plugging in its connector, the actuator will go out of range and be inoperative.
Always attach the HVAC actuator to the case before installing the electrical connector.
If an actuator is out of range it may be possible to bring it back into range by following the procedure below:
Please follow this diagnostic or repair process thoroughly and complete each step. If the condition exhibited is resolved without completing every step, the remaining steps do not need to be performed.
Did you perform the Diagnostic System Check?
Go to Step 2
Go to Diagnostic System Check
Verify that the heating is insufficient.
Is the heating sufficient?
Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems
Go to Step 3
Inspect for the following conditions:
Does the malfunction still exist?
Go to Step 4
Go to Step 29
Is the airflow high?
Go to Step 5
Go to Step 8
Does the airflow change with different blower speeds?
Go to Step 6
Go to Step 12
Perform the System Performance Test. Refer to System Performance Test
Is the heater output temperature correct?
Go to Step 7
Go to Step 13
Is the repair complete?
Perform the function test. Refer to System Performance Test
Go to Step 9
Check the airflow from the vent outlets.
Is the airflow from the vent outlets high?
Go to Step 10
Go to Step 18
Move the defroster and/or the vent valve to the HEATER mode.
Is the defroster airflow correct?
Go to Step 11
Go to Step 19
Is the temperature valve fully closed?
Go to Step 14
Go to Step 23
Is the air temperature around both hoses at least at the specified value?
Go to Step 15
Go to Step 24
Were the hoses properly installed?
Go to Step 16
Go to Step 26
Go to Step 17
Replace the heater core. Refer to Heater Core Replacement in Heater and Ventilation -- Non-A/C.
Is the defroster airflow not present or low?
Go to Step 20
Inspect for airflow obstructions at the blower inlet and plenum.
Did you find and correct a condition?
Go to Step 21
Is a change in the airflow audible?
Go to Step 22
Go to Step 27
Check for an airflow obstruction between the blower and the system outlets.
Check the thermostat for proper installation and seating.
Is the thermostat properly installed and seated?
Go to Step 28
Go to Step 25
Reinstall the thermostat.
Properly reinstall the hoses.
Inspect the following components:
Replace the thermostat.
Operate the system in order to verify the repair.
Did you correct the condition?