Schematic Reference: HVAC Schematics

Connector End View Reference: HVAC Connector End Views

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

Did you perform the HVAC Diagnostic System Check?

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Go to Step 2

Go to Diagnostic System Check - HVAC Systems - Manual

1. Turn ON the ignition, with the engine OFF.
2. Place the blower motor switch in the OFF position.

Is the blower motor OFF?

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Go to Step 3

Go to Blower Motor Always On

Place the blower motor switch in each speed position.

Does the blower motor operate in any speed position?

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Go to Step 4

Go to Blower Motor Inoperative

Does the blower motor operate in each speed position?

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Go to Step 5

Go to Blower Motor Malfunction

Are all of the HVAC control module controls except for the blower motor inoperative?

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Go to Step 14

Go to Step 6

1. Place the blower motor switch in the maximum speed position.
2. Place the mode switch in the vent position.
3. Place the recirculation switch in the ON position.
4. Observe the recirculation door.
5. Place the outside air switch in the ON position.

Does the recirculation door move from the recirculation to the outside air position?

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Go to Step 7

Go to Air Recirculation Malfunction

1. Place the blower motor switch in the maximum speed position.
2. Place the mode switch in each mode position.

Does air flow sufficiently from the proper air distribution outlets for each selected mode position?

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Go to Testing for Intermittent Conditions and Poor Connections in Wiring Systems

Go to Step 8

Inspect the air delivery system for the following conditions:

Did you find and correct the condition?

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Go to Step 23

Go to Step 9

Inspect the mode door and the mode actuator for the following conditions:

Did you find and correct the condition?

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Go to Step 23

Go to Step 10

1. Turn OFF the ignition.
2. Disconnect the mode actuator.
3. Turn ON the ignition, with the engine OFF.
4. Probe the ignition 3 voltage circuit of the mode actuator with a test lamp that is connected to a good ground.

Does the test lamp illuminate?

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Go to Step 11

Go to Step 20

Test the ground circuit of the mode actuator for an open or for a high resistance. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 23

Go to Step 12

12

1. Turn OFF the ignition.
2. Reconnect the mode actuator.
3. Turn ON the ignition with the engine OFF.
4. Measure the voltage from the mode door control circuit of the mode actuator to a good ground.
5. Observe the control circuit voltage of the mode door .
6. Place the mode switch in each mode position.

Does the voltage measure near the specified values for each mode position?

Vent: 0.2V, Bi-Level: 3.1V, Floor: 5.0V Mix-Blend: 8.9V, Defrost: 11.8V

Go to Step 18

Go to Step 13

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

Did you find and correct the condition?

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Go to Step 23

Go to Step 19

14

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

Did you find and correct the condition?

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Go to Step 23

Go to Step 15

Test the battery positive voltage circuit of the HVAC control module for an open or for a high resistance. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 23

Go to Step 16

Test the ground circuit of the HVAC control module for an open or for a high resistance. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 23

Go to Step 17

Test the off blower motor control circuit of the HVAC control module for a short to voltage. Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 23

Go to Step 19

Inspect for bad connections at the harness connector of the mode actuator. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 23

Go to Step 21

Inspect for bad connections at the harness connector of the HVAC control module. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?

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Go to Step 23

Go to Step 22

Repair the ignition 3 voltage circuit of the mode actuator. Refer to Wiring Repairs in Wiring Systems.

Did you complete the repair?

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Go to Step 23

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Replace the mode actuator. Refer to Mode Actuator Replacement .

Did you complete the replacement?

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Go to Step 23

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Replace the HVAC Control module. Refer to HVAC Control Module Replacement .

Did you complete the replacement?

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Go to Step 23

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Operate the system in order to verify the repair.

Did you correct the condition?

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System OK

Go to Step 8