MODEL IDENTIFICATION
Adjustment and repair procedures in this article are referred to by series designation rather than by model name. Following table lists General Motors model name and series designation.
| Model | Designation |
|---|---|
| Blazer, Pickup, Sierra, Suburban & Yukon | "C" & "K" Series |
GENERAL MOTORS MODEL DESIGNATION
DESCRIPTION
System is a blend-air type. Outside air is heated and then mixed with cooler outside air to attain desired temperature. System consists of a blower, air inlet assembly, heater air distributor assembly and heater control panel.
Blower, air inlet assembly and heater hoses are located on engine side of firewall; heater core and distributor duct are on passenger side. Coolant circulation keeps heater core hot at all times.
Operation of blower motor is controlled by fan switch. Motor is connected in series with fan switch and blower resistor assembly.
On Suburban, an auxiliary heater is available for heating rear of vehicle. The auxiliary heater is independent of standard heater and has its own set of controls. Heater hoses connect at standard heater core and extend to auxiliary heater core. A vacuum-operated heater control valve is installed in inlet line in engine compartment to cut off coolant flow when heat is not desired.