Too Hot in Vehicle - Auxiliary With Heat and A/C
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step ensures that the primary HVAC system is functioning properly.
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If the condition does not occur when an A/C request has been made then you must bypass the A/C performance test procedures.
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Performing the Air Conditioning System Performance Test ensures that the A/C system is operating properly for further testing.
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This step ensures that the rear auxiliary HVAC control module is able to move the auxiliary air temperature actuator.
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This step ensures that the front auxiliary HVAC control assembly is able to move the auxiliary air temperature actuator.
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There is 2 ignition 3 voltage circuits for the rear HVAC control assembly. The circuit that needs to be tested is the circuit that supplies ignition 3 voltage to the auxiliary HVAC control processor. If this circuit is open the auxiliary mode and air temperature actuators will not move with in there full range of motion.
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There is 2 ignition 3 voltage circuits for the rear HVAC control assembly. The circuit that needs to be tested is wired between the left I/P fuse block and the rear HVAC control assembly.
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The circuit that is to be tested is wired between the rear auxiliary HVAC control assembly and the auxiliary HVAC control processor. The circuit is the position signal from the rear auxiliary HVAC control assembly for the auxiliary air temperature actuator. The circuit only provides a reference when the front auxiliary HVAC control assembly is in the AUX position.
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The circuit that is to be tested is wired between the front auxiliary HVAC control assembly and the auxiliary HVAC control processor. The circuit is the position signal from the rear auxiliary HVAC control assembly for the auxiliary air temperature actuator. The circuit only provides a reference when the front auxiliary HVAC control assembly is in any other position than AUX position.
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This step checks the output of the auxiliary HVAC control processor to the auxiliary air temperature actuator.
Step | Action | Values | Yes | No | ||||||||||
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Schematic Reference: HVAC Schematics Connector End View Reference: HVAC Connector End Views DEFINITION: Auxiliary air temperature can not be adjusted from one or both auxiliary controls or auxiliary cooling is insufficient. | ||||||||||||||
1 | Did you review the HVAC operation and perform the necessary inspections? | -- | Go to Step 2 | |||||||||||
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Important:: The auxiliary HVAC control assembly cannot request A/C compressor operation. An A/C request must be generated by the HVAC control module to provide cooled airflow through the auxiliary system. Does the HVAC control module operate and provide sufficient cooling? | -- | Go to Step 3 | Go to Too Hot in Vehicle | |||||||||||
3 |
Does the auxiliary blower motor operate at all? | -- | Go to Step 4 | |||||||||||
4 | Does the auxiliary blower motor operate correctly for each speed position? | -- | Go to Step 5 | |||||||||||
Does the Auxiliary Too Hot In Vehicle concern occur when A/C cooling is desired? | -- | Go to Step 6 | Go to Step 7 | |||||||||||
Perform the air conditioning (A/C) system performance test. Refer to Air Conditioning (A/C) System Performance Test . Did you find and correct the condition? | -- | Go to Step 32 | Go to Step 7 | |||||||||||
Does the auxiliary air temperature actuator drive shaft rotate at all? | -- | Go to Step 8 | Go to Step 11 | |||||||||||
Does the auxiliary air temperature actuator drive shaft rotate at all? | -- | Go to Step 9 | Go to Step 15 | |||||||||||
Test the ignition 3 voltage circuit that is wired between the rear auxiliary HVAC control assembly to the auxiliary HVAC control processor for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 32 | Go to Step 10 | |||||||||||
10 | Inspect the auxiliary air temperature door and the auxiliary air temperature actuator for the following conditions:
Did you find and correct the condition? | -- | Go to Step 32 | Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems | ||||||||||
11 |
Does the auxiliary air temperature actuator drive shaft rotate at all? | -- | Go to Step 13 | Go to Step 12 | ||||||||||
Test the ignition 3 voltage circuit of the rear auxiliary HVAC control assembly for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 32 | Go to Step 18 | |||||||||||
13 | Test the rear auxiliary temperature door control circuit of the rear auxiliary HVAC control assembly for an open, high resistance, a 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 32 | Go to Step 14 | ||||||||||
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Important:: The rear auxiliary HVAC control assembly connector must be connected to correctly perform test.
Does the voltage change and measure within the specified range? | 0-12 V | Go to Step 27 | Go to Step 25 | |||||||||||
15 | Test the ignition 3 voltage circuit of the front auxiliary HVAC control assembly 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 32 | Go to Step 16 | ||||||||||
16 | Test the auxiliary air temperature door position signal circuit of the front auxiliary HVAC control assembly for an open, high resistance, a 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 32 | Go to Step 17 | ||||||||||
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Important:: The front auxiliary HVAC control assembly connector must be connected to correctly perform test.
Does the voltage change and measure within the specified range? | 0-12 V | Go to Step 27 | Go to Step 26 | |||||||||||
18 | Test the ignition 3 voltage circuit of the auxiliary HVAC control processor 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 32 | Go to Step 19 | ||||||||||
19 | Test the ignition 3 voltage circuit of the auxiliary 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 32 | Go to Step 20 | ||||||||||
20 | Test the ground circuit of the auxiliary air temperature actuator for an open. Refer to Circuit Testing and Wiring Repairs in Wiring Systems. Did you find and correct the condition? | -- | Go to Step 32 | Go to Step 21 | ||||||||||
21 | Test the auxiliary air temperature door control circuit of the auxiliary air temperature actuator for an open, high resistance, a 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 32 | Go to Step 22 | ||||||||||
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Important:: The auxiliary HVAC control processor, front and rear auxiliary HVAC control assembly connectors must be connected to correctly perform test.
Does the voltage change and measure within the specified range? | 0-12 V | Go to Step 23 | Go to Step 27 | |||||||||||
23 | Inspect for poor connections at the harness connector of the auxiliary 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 32 | Go to Step 24 | ||||||||||
24 | Inspect the auxiliary 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 32 | Go to Step 28 | ||||||||||
25 | Inspect for poor connections at the harness connector of the rear auxiliary 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 32 | Go to Step 29 | ||||||||||
26 | Inspect for poor connections at the harness connector of the front auxiliary 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 32 | Go to Step 30 | ||||||||||
27 | Inspect for poor connections at the harness connector of the auxiliary HVAC control processor. 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 32 | Go to Step 31 | ||||||||||
28 | Replace the auxiliary air temperature actuator. Refer to Auxiliary Temperature Valve Actuator Replacement . Did you complete the replacement? | -- | Go to Step 32 | -- | ||||||||||
29 | Replace the rear auxiliary HVAC control assembly. Refer to Auxiliary Heater and Air Conditioning Control Replacement - Rear . Did you complete the replacement? | -- | Go to Step 32 | -- | ||||||||||
30 | Replace the front auxiliary HVAC control assembly. Refer to Auxiliary Heater and Air Conditioning Control Replacement - Front . Did you complete the replacement? | -- | Go to Step 32 | -- | ||||||||||
31 | Replace the auxiliary HVAC control processor. Refer to Auxiliary HVAC Control Processor Replacement . Did you complete the replacement? | -- | Go to Step 32 | -- | ||||||||||
32 | Operate the system in order to verify the repair. Did you correct the condition? | -- | System OK | Go to Step 2 | ||||||||||
Too Hot in Vehicle - Auxiliary A/C Only
Test Description
The numbers below refer to the step numbers on the diagnostic table.
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This step ensures that the primary HVAC system is functioning properly.
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Performing the Air Conditioning System Performance Test ensures that the A/C system is operating properly for further testing.
Step | Action | Values | Yes | No |
|---|---|---|---|---|
Schematic Reference: HVAC Schematics Connector End View Reference: HVAC Connector End Views DEFINITION: Auxiliary air temperature can not be adjusted from one or both auxiliary controls or auxiliary cooling is insufficient. | ||||
1 | Did you review the HVAC operation and perform the necessary inspections? | -- | Go to Step 2 | |
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Important:: The auxiliary HVAC control assembly cannot request A/C compressor operation. An A/C request must be generated by the HVAC control module to provide cooled airflow through the auxiliary system. Does the HVAC control module operate and provide sufficient cooling? | -- | Go to Step 3 | Go to Too Hot in Vehicle | |
3 |
Does the auxiliary blower motor operate at all? | -- | Go to Step 4 | |
4 | Does the auxiliary blower motor operate correctly for each speed position? | -- | Go to Step 5 | |
Perform the air conditioning (A/C) system performance test. Refer to Air Conditioning (A/C) System Performance Test . Did you find and correct the condition? | -- | Go to Step 6 | ||
6 | Operate the system in order to verify the repair. Did you correct the condition? | -- | System OK | Go to Step 2 |
