I have a 2004 F150 5.4 and the temp gauge went stopped working couple weeks ago along with the check engine light coming on. I checked it and got a P1289. I changed the Cylinder head temp sensor and it did not fix the problem. Anyone ran into this or have any ideas. All the wires look fine and it just started this out of the blue.

 

This is from the code list.

P1289 Cylinder Head Temp Sensor High Input

 

Yea that is it, I replaced the sensor but still getting the same thing, any ideas???????????

 

im getting this same problem actually, except that its also messing with my A/C. When i start my truck it will go up but go back down two seconds later, and will say check gauges. Im also getting that P1289 code. Acouple weeks prior, the gauge would act up like 2 or 3 times a day. When the gauge was working properly my a/c compressor would kick on and everything seemed dandy, but when it would go down and say check gauges, it would kick off and just put out hot air. Im puzzled on this to as i have already replaced the ECT and the CHT sensors. if you have heard anything regarding your problem, let me know, thanks!!

 

Possible Causes•Harness or connectors (The A/F sensor 1 circuit is open or shorted.)
•Air fuel ratio (A/F) sensor 1
•Air fuel ratio (A/F) sensor 1 heater
•Fuel pressure
•Fuel injector
•Intake air leaks
•Exhaust gas leaks
•PCV
•Mass air flow sensor


Make sure the gas cap is sealed. Also, check the fuel injectors. One could be sticking closed.

 

Same here, no ac, no temp guage and check engine with same code? Any updates?

 

Fixed, it was the CHT wiring.