For 1990-2009 cars

Step | Action | Yes | No
--- | --- | --- | ---
DEFINITION: Odour originating or noticed through the HVAC system.
1 | Were you sent here from Symptoms or another diagnostic table? | Go to Step 2 | Go to Symptoms - HVAC Systems - Automatic or Symptoms - HVAC Systems - Manual .
2 |

1. Sit inside the vehicle.
2. Close all of the doors and windows.
3. Start the engine.
4. Allow the engine idle at normal operating temperature.
5. Select the maximum blower speed.
6. Select the PANEL air outlet mode.
7. Select the coldest temperature setting.
8. Cycle through all of the blower speeds, modes, and temperatures to define what type of odour is present.

• | Musty smell

• | Coolant smell

• | Oil smell

Does the odour have a musty smell?

Go to Step 3

Go to Step 8

3 | Inspect the HVAC module assembly filter and the air inlet grille for debris. Is debris present? | Go to Step 4 | Go to Step 5
4 | Remove any debris. Is the action complete? | Go to Step 15 | --
5 | Inspect for wet carpeting. Is the carpet wet? | Go to Step 6 | Go to Step 14
6 |

1. Inspect for the following conditions:

• | Water leaks around the windshield.

• | Leaks around the door seals.

2. Turn blower motor fan to MAX.

Caution: Refer to Vehicle Lifting Caution in the Preface section.

3. Raise the vehicle.
4. Check for air flow from drain, LHS of vehicle above transmission.

Is a leak present?

Go to Step 7

Go to Step 14

7 | Repair the leak as necessary. Is the repair complete? | Go to Step 15 | --
8 | Does the odour have a coolant smell? | Go to Step 9 | Go to Step 12
9 | Inspect the cooling system for leaks. Refer to Loss of Coolant . Is a leak present? | Go to Step 10 | Go to Step 12
10 | Inspect for coolant leaking inside the vehicle or for a film build-up on the windshield. Is the condition present? | Go to Step 11 | Go to Step 15
11 | Replace the heater core. Refer to Heater Core Replacement . Is the repair complete? | Go to Step 15 | --
12 | Does the odour have an oily smell? | Go to Step 13 | Go to Step 15
13 |

1. Inspect the engine compartment for any leaks. Refer to the following procedures:

• | Oil Leak Diagnosis for 3.6L engine, or Oil Leak Diagnosis for 6.0L engine.

• | Fluid Leak Diagnosis , or Transmission Fluid Leak Diagnosis or Transmission Fluid Leak Diagnosis.

• | Power Steering Fluid Leaks.

2. Repair any oil leaks.

Is the repair complete?

Go to Step 15

--

14 | A musty odour can be caused by mould or mildew build-up on the evaporator or the heater core or inside of the HVAC module assembly. Refer to Odor Correction . Is the action complete? | Go to Step 15 | --
15 | Operate the system in order to verify the repair. Did you find and correct the condition? | System OK | Go to Step 2