For 1990-2009 cars

## Heat Excessive Heat Mode

Step | Action | Yes | No
--- | --- | --- | ---
1 | Turn the blower speed from OFF to each of the following positions with the ignition switch in the ON position:

1. LOW
2. MEDIUM 1
3. MEDIUM 2
4. HIGH
5. OFF

Does the blower motor speed increase at each speed level when you turn the blower speed switch towards HIGH?

Go to Step 2

Go to HVAC System Check

2 |

1. Set the mode control to the HEAT position.
2. Set the temperature control to the hottest position.
3. Set the blower speed to HIGH.
4. Turn the ignition switch to ON.
5. Inspect for airflow out of the heater outlet.

Is there high airflow from the heater outlet?

Go to Step 3

Go to Step 4

3 |

1. Inspect the temperature control cable and the linkages.
2. Adjust the temperature control cable. Refer to Temperature Control Cable Replacement .

Is the repair complete?

Go to Step 5

--

4 |

1. Inspect the mode control cable and the linkages.
2. Adjust the mode control cable. Refer to Mode Control Cable Replacement .

Is the repair complete?

Go to Step 5

--

5 | Perform the function test. Refer to Function Test . Is the repair complete? | System OK | --

## Heat Excessive Vent Mode

Step | Action | Yes | No
--- | --- | --- | ---
1 |

1. Turn the ignition switch to the LOCK position.
2. Test the temperature control cable operation by moving the temperature control to the hottest position, then rapidly to the coldest position.

Do you hear the temperature door close at each end of the door's travel?

Go to Step 2

Go to Step 3

2 |

1. Set the mode control to the VENT position.
2. Set the temperature control to the coldest position.
3. Set the blower speed to HIGH.
4. Start the engine, and warm-up the engine.
5. Measure the air temperature at the blower inlet with a thermometer.
6. Measure the air temperature at the vent outlet with a thermometer.

Is the temperature difference 5°C (9°F) or greater?

Go to Step 4

Go to Step 5

3 |

1. Inspect the temperature control cable and the linkages.
2. Adjust the temperature control cable. Refer to Temperature Control Cable Replacement .

Is the repair complete?

Go to Step 5

--

4 |

• | Inspect for hot air leaks from the engine compartment to the blower air inlet.

• | Inspect the heater case for leaks.

• | Repair the heater case, as necessary.

Is the repair complete?

Go to Step 5

--

5 | Perform the function test. Refer to Function Test . Is the repair complete? | System OK | --