E500 is triggered when the temperature of the outdoor unit’s inverter heatsink climbs above a safe threshold. The heatsink’s job is to draw heat away from the power electronics driving the compressor, and when it can’t keep up, the system shuts down to prevent damage.
This fault is most commonly linked to airflow problems around the outdoor unit rather than a failed component, since restricted airflow makes it much harder for the heatsink to stay cool. It’s one of the more DIY-friendly faults to at least start investigating yourself.
Send us the code and a photo of the display, and a Ford & Doonan technician will get back to you. Please don't reset the unit before you take the photo.
(08) 9331 8800