Functional Test/Check

Functional Test Chart:

INSPECTION OF THE SYSTEM
^ If a malfunction in the system is suspected, check the following:
1. Check outer surfaces of radiator core to be sure air flow is not blocked by dirt, leaves or other foreign material.
2. Restrictions or kinks in the heater core, hoses, tubes, etc.
3. Blower motor operation.
4. Coolant leaks.
5. Check all air ducts for leaks or restrictions. Low air flow rate may indicate a restricted heater core.
6. Cooling fan for normal operation.
7. Coolant thermostat for normal operation.
8. Temperature door for proper operation. Refer to System Diagnostic Charts. Without A/C

FUNCTIONAL TEST
^ To help in determining whether or not the electrical and vacuum systems are operating properly, perform the following:
1. Operation of the blower fan at all 4 speeds with the (mode) lever in any position except OFF. (The blower will not operate in any speed with the mode lever in the OFF position.)
2. Operation of the control selector (mode) lever to distribute air from the appropriate outlets indicate proper operation. The system will default to air flow in several modes if a vacuum system malfunction exists.

^ Refer to A/C and Heater Functional Test Chart (see image) for further testing of operation.