Evaporator Core

Leaks in the evaporator core are difficult to find. The core is inside an encapsulated module. The core is inaccessible to leak detector devices. Use the following procedure in order to test the core:
1. Turn the blower fan on HIGH for 15 seconds. Shut the fan off.
2. Wait 10 minutes.
3. Remove the blower motor or the blower motor resistor.
4. Insert the leak detector probe into the opening. Get the probe as close as possible to the evaporator.
A solid alarm on the detector indicates a leak
5. If possible, use a flashlight in order to visually inspect the core face for evidence of refrigerant oil.