Schematic Reference: HVAC Schematics

Connector End View Reference: HVAC Connector End Views

DEFINITION: Air does not flow correctly from the auxiliary air distribution outlets.

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

Go to Step 2

Go to Symptoms - HVAC Systems - Manual

1. Turn ON the ignition, with the engine OFF.
2. Place the front auxiliary HVAC control assembly blower control in the OFF position.
3. Place the rear auxiliary HVAC control assembly blower control in the OFF position.

Is the auxiliary blower motor OFF?

Go to Step 3

Go to Blower Motor Always On

Place the front auxiliary HVAC control assembly blower control in each speed position.

Does the auxiliary blower motor operate at all?

Go to Step 4

Go to Blower Motor Inoperative

Does the auxiliary blower motor operate correctly for each speed position?

Go to Step 5

Go to Blower Motor Malfunction

5

1. Turn ON the ignition, with the engine OFF.
2. Select AUX on the front auxiliary HVAC control assembly.
3. Observe the drive shaft of the auxiliary mode actuator.
4. Adjust the rear auxiliary mode switch.

Does the auxiliary mode actuator drive shaft rotate at all?

Go to Step 6

Go to Step 8

6

1. Place the front auxiliary blower motor switch in any position other than AUX on the front auxiliary HVAC control assembly.
2. Place the front auxiliary mode switch from the floor to upper outlets position.

Does the auxiliary mode actuator drive shaft rotate at all?

Go to Step 7

Go to Step 12

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 28

Go to Step 20

1. Place the front auxiliary blower motor switch in any position other than AUX on the front auxiliary HVAC control assembly.
2. Place the front auxiliary mode switch from the floor to upper outlets position.

Does the auxiliary mode actuator drive shaft rotate at all?

Go to Step 10

Go to Step 9

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 28

Go to Step 15

Test the rear auxiliary mode 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 28

Go to Step 11

Important:: The rear auxiliary HVAC control assembly connector must be connected to correctly perform test.

1. Turn ON the ignition, with the engine OFF.
2. Measure the voltage from the rear auxiliary mode door control circuit of the rear auxiliary HVAC control assembly to a good ground. Refer to Circuit Testing in wiring systems.
3. Place the front auxiliary mode switch from the floor to upper outlets position.

Does the voltage change from 0 to 12 volts?

Go to Step 21

Go to Step 23

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 Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 28

Go to Step 13

Test the auxiliary mode 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 Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 28

Go to Step 14

Important:: The front auxiliary HVAC control assembly connector must be connected to correctly perform test.

1. Turn ON the ignition, with the engine OFF.
2. Measure the voltage from the auxiliary mode door position signal circuit of the front auxiliary HVAC control assembly to a good ground. Refer to Circuit Testing in Wiring Systems.
3. Place the front auxiliary mode switch from the floor to upper outlets position.

Does the voltage change between 0 and 12 volts?

Go to Step 21

Go to Step 22

Test the ignition 3 voltage circuit of the auxiliary HVAC control processor for an open or a high resistance. Refer to Circuit Testing and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 28

Go to Step 16

Test the ignition 3 voltage circuit of the auxiliary mode actuator for an open or a high resistance. Refer to Circuit Testing and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 28

Go to Step 17

Test the ground circuit of the auxiliary mode actuator for an open. Refer to Circuit Testing and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 28

Go to Step 18

Test the auxiliary mode door control circuit of the auxiliary mode actuator for an open, high resistance, a short to ground or short to voltage. Refer to Circuit Testing and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 28

Go to Step 19

Important:: The auxiliary HVAC control processor, front and rear auxiliary HVAC control assembly connectors must be connected to correctly perform test.

1. Turn ON the ignition, with the engine OFF.
2. Place the front auxiliary blower motor switch in any position other than AUX on the front auxiliary HVAC control assembly.
3. Measure the voltage from the auxiliary mode door control circuit of the auxiliary mode actuator to a good ground. Refer to Circuit Testing in Wiring Systems.
4. Place the front auxiliary mode switch from the floor to upper outlets position.

Does the voltage change between 0 and 12 volts?

Go to Step 20

Go to Step 21

Inspect for poor connections at the harness connector of the auxiliary mode actuator. Refer to Wiring Repairs and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 28

Go to Step 24

Inspect for poor connections at the harness connector of the auxiliary HVAC control processor. Refer to Wiring Repairs and Connector Repairs in Wiring Systems.

Did you find and correct the condition?

Go to Step 28

Go to Step 25

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 28

Go to Step 26

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 28

Go to Step 27

Replace the auxiliary mode actuator. Refer to Auxiliary Mode Valve Actuator Replacement .

Did you complete the replacement?

Go to Step 28

--

Replace the auxiliary HVAC control processor. Refer to Auxiliary HVAC Control Processor Replacement .

Did you complete the replacement?

Go to Step 28

--

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 28

--

Replace the HVAC control assembly - auxiliary rear. Refer to Auxiliary Heater and Air Conditioning Control Replacement - Front .

Did you complete the replacement?

Go to Step 28

--

Operate the system in order to verify the repair.

Did you correct the condition?

System OK

Go to Step 2