Taylor D

(03 V6 Mustang, Automatic)
Went to AutoZone and had them run my Check Engine Light:

P1289- Cylinder Head Temperature Sensor Circuit High Input
P1290- Cylinder Head Temperature Sensor Circuit Low Input

What would be causing these codes to be on?

Also my Temperature Gauge stopped working and my A/C stopped blowing cold.

jwog666

the high code usually indicates that the circuit as disconnected or went open, the low code usually indicates that the circuit is shorted, inspect the wiring and if that checks out suspect the sensor to be faulty. the ac will stop working if the cht sensor quits reading correctly, its part of the failure strategy.