Function Test. GMC Truck Savana 2000

For 1990-2009 cars only

Makes 🢒 GMC_Truck 🢒 2000 🢒 Savana 🢒 Body and Accessories 🢒 Wiring Systems 🢒 Function Test

Conduct the Function Test of the heater system with the vehicle idling. Before beginning the test, allow the vehicle to idle until the coolant is hot and the thermostat is open. The coolant temperature should be 90°C (194°F). If you find a problem during any intermediate step of the Function Test, complete the test before beginning any needed repairs.

Function Test

Control Settings			System Response
Mode Control	Temperature Control	Blower Switch	Blower Speed	Heater Outlets	Instrument Panel Outlets	Defroster Outlets	See Remarks
OFF	COLD(BLUE)	LOW-HIGH	OFF	No Air Flow	No Air Flow	No Air Flow	1,3
VENT	COLD	HIGH	HIGH	No Air Flow	Air Flow	No Air Flow	1,2,3,4,6
BLEND (HEATER/VENT)	COLD	HIGH	HIGH	Air Flow	Air Flow	No Air Flow	1,2,3,5,6
HEATER	HOT (RED)	HIGH	HIGH	Air Flow	No Air Flow	Minimum Air Flow	1,2,3,6
BLEND (HEATER/DEFROST)	HOT	HIGH	HIGH	Air Flow	No Air Flow	Air Flow	1,2,3,6
DEFROST	HOT	HIGH	HIGH	Minimum Air Flow	No Air Flow	Air Flow	1,2,3,6
Remarks The speed of the blower must increase as the fan switch moves from the LOW position to the HIGH position. Feel the engagement of the detent in each mode. Check for airflow at the side window defogger outlets. Air temperature from the ducts should be nearly the same temperature as the outside air. All air should be hot. Move the temperature knob from the full HOT (red) position to the full COLD (blue) position. Ensure that the air temperature drops back to nearly the temperature of the outside air.

Function Test

Remarks