TCL Air Conditioner Error Codes | Troubleshooting Error Codes Problem TCL AC Error Codes:- E0 Problem:-Indoor/outdoor communication fault TCL AC Error Codes:- EC Problem:-Outdoor communication fault TCL AC Error Codes:- E1 Problem:-Room temperature sensor (IRT) TCL AC Error Codes:- E2 Problem:-Indoor pipe (coil) temperature sensor (IPT) TCL AC Error Codes:- E3 Problem:-Outdoor pipe (coil) temperature