Frosty, Toasty or Roasty?
The Four Keys
You need four things to keep the heat flowing in the winter.
What’s wrong, and what will fix it?
1. Lack of heat:
a.Do you have good coolant flow through the heater core? Check your cooling system maintenance manual. Service cooling system and flush water side of heater core, if necessary.
b.Does the engine reach operating temperature? Check gauge, replace thermostat or seals as necessary.
c.Does temperature door or water valve force full air or water flow through heater core? Repair/ replace cable or actuator motor, or water flow control valve.
d.Do you have clogged filters, air ducts or core fins? Clean/replace filters, disassemble and vacuum out ducts or core fins, as necessary.
2. Airflow does not shift to proper floor, dash or defrost outlet:
a. Inspect ducting around door for obstructions.
b.Check and adjust/repair cable clamps or cable.
c.Inspect wiring to actuator motor and repair if necessary.
d.Test and then replace actuator motor or in-dash controller
3. Blower fails to operate in any speed setting:
a.Test for voltage to motor. If non-existent, test/replace or repair wiring (including ground if used), fuse and dash switch. If voltage exists and ground is intact,
For Further Information Contact:
Peterbilt Motors Co.
Kenworth Truck Co.
International Truck and Engine Corp.
Mack Trucks, Inc.
Volvo Trucks North America