Functional Test/Check

DIAGNOSIS
To diagnose the Electronic Climate Control (ECC) System in the shortest time and with the least amount of effort, it is important to know how a properly functioning system will perform. For diagnosis of all ECC functions, refer to CLIMATE CONTROL DIAGNOSIS.

FUNCTIONAL TEST

The following operational test sequence will aid in determining whether the ECC system electrical, air distribution, vacuum or refrigeration systems are functioning properly. The ambient temperature should be at least 4°C (40°F); the engine should be warmed to normal operating temperature.

1. Set temperature to 16°C (60°F). Turn the A/C system off and on using the 'OFF' and 'AUTO' buttons on the control panel.
^ The compressor should turn on and off with every push of the 'OFF/AUTO' BUTTONS.
2. With the A/C system on, switch the mode buttons to their various positions and check which air outlets release air.

Important Switching modes is not an instantaneous reaction and it may take one or two minutes to complete the mode change.

^ The actual outlets employed when each mode push button is pushed should correspond to the outlets on the push button.

3. Check to make sure the blower fan is operating properly; run through all fan speed settings at various temperatures to check the function of the blower motor.

Successful completion of these test procedures indicates that the electrical and vacuum-controller air distribution systems are functioning properly.