Insufficient Heating of the Passenger Compartment
- Inspect for the incorrect operation of the controls.
Advise the driver of the proper operation of the controls.
- Inspect the engine for low engine coolant level.
Perform the following steps, as necessary:
| • | Inspect the engine for coolant leaks. |
| • | Run the engine in order to clear any air locks. |
- Inspect for a faulty engine thermostat.
Replace the thermostat, if necessary. Refer to
Engine Coolant Thermostat Replacement
in Engine Cooling.
- Inspect for a kinked heater hose.
Perform the following steps, as necessary:
| • | Straighten the heater hose. |
- Inspect for obstructed heater core tubes.
An obstruction usually causes a squishing noise in the heater core.
Perform the following steps, as necessary:
| • | Remove any foreign material from the heater core. |
- Inspect for one of the following conditions:
| • | A faulty blower circuit |
| • | Repair or replace faulty wires or connections. |
Insufficient Heating of the Rear Seat Area
- Inspect for the incorrect operation of the controls.
Advise the driver to use high blower speed in order to force air into
the rear of the passenger compartment.
- Inspect for an obstruction on the floor.
Inspect for the following conditions under the front seat:
Insufficient Heating
- Inspect the duct work for the following conditions:
| • | The proper installation |
- Inspect the blower operation.
- Inspect the following components for the proper installation and
the proper operation:
