Heat Excessive. Pontiac Sun Runner - 2WD (Canada) 1998

For 1990-2009 cars

## Heat Excessive Heater Mode

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---

1

1. Turn the ignition switch to ON.
2. Turn the blower switch to the following settings:

2.1. | From OFF to LO

2.2. | To MED 1

2.3. | To MED 2

2.4. | To HI

2.5. | Back to OFF

Does the blower motor speed increase at each speed level as the blower speed selector switch is moved towards HI and then decrease as the switch is moved towards LO?

--

Go to Step 3

Go to Step 2

2 | Refer to Heater Blower Controls System Check for blower motor diagnosis. Is the action complete? | -- | Go to Step 6 | --

3

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

Is the airflow low or nonexistent from the heater outlet?

--

Go to Step 4

Go to Step 5

4

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

Is the action complete?

--

Go to Step 6

--

5

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

Is the action complete?

--

Go to Step 6

--

6 | Perform the functional test. Refer to Function Test . Is the action complete? | -- | System OK | --

## Heat Excessive Vent Mode

Step | Action | Value(s) | Yes | No
--- | --- | --- | --- | ---

1

1. Turn the ignition switch to LOCK.
2. Move the temperature control to full HOT, then rapidly to full COLD.

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

--

Go to Step 2

Go to Step 4

2

1. Set the mode to VENT.
2. Set the temperature control to full COLD.
3. Start the engine.
4. Let the engine warm-up.
5. With a thermostat, test the air temperature at the blower inlet.
6. With a thermostat, test the air temperature at the vent outlet.

Is the temperature difference the same or less than the specified value?

5°C (9°F)

Go to Step 3

Go to Step 5

3 | Inspect the heater case for leaks. Repair the heater case as necessary. Is the action complete? | -- | Go to Step 6 | --

4

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

Is the action complete?

--

Go to Step 6

--

5 | Inspect for hot air leaks from the engine compartment to the blower air inlet. Repair as necessary. Is the action complete? | -- | Go to Step 6 | --
6 | Perform the functional test. Refer to Function Test . Is the action complete? | -- | System OK | --