The read out project F : FF what is wrong

It means you haven't read the user manual
APPLIANCE911

could be the exterior temp sender unit these are usually mounted on the underside of the drivers door mirror or the display itself may be reading wrong get the OBD codes read as may tell which sensor is not reading correctly

The temp sensor, is a thermistor resistor supplying restricted voltage to the gauge depending on the heat of the engine, if it has gone faulty (close circuit) the gauge will read hot all the time. You need to find the sensor, generally near the top of the engine, thermostat area and unplug it, the gauge will then not read. Replace the sensor. (WHEN THE ENGINE IS COLD)

How is it reading wrong ?

Hello williamcole7: My name is Roger and I will help you. The code 888 is a test code. This tests the L e d's of the dash cluster. All segments must light so you can read all numbers. The 70 code means the system is ready and able to function. The ff code is a current BCM code and is happening at the moment. The f 40 code is a BCM history code and means it was a stored problem or something that has happened. The f 40 code is for a air mix door problem. THe BCM would set this if you had an A/C problem. The E 48 code deals with the EGR system fault. I would check for a vacuum leak at the EGR solenoid. The hose is prone to deterioration do to heat from the engine. Code E52 deal with loss of voltage. A dead battery or a disconnected battery cable will always set this code. None of these codes will keep the car from running.The repair schematics are to extensive to send in a reply. Should you need further help ao assistance I will be glad to help. Please rate the answer. Thank You for using Fix Ya. Roger

The reason it did not read hot, on your temp. gauge, is cause your temp. sensor read's coolant or water temp only, not air, if cooling system is empty, coolant temp. sensor will not read, like an air temp. sensor well, more the likely there could be a coolant leak for cooling system to be empty, also could have damage your cylinder's head's, need to have a block test and cylinder compression test done to fine out if head's are damage.

Sounds like iced up evaporator fan/coils.FF- frosted freezer?er-no air flow to Fresh Food compartment?

it may afect the climate control to operate right,
try to locate the temperature sensor than most times is in the lower side of the wilshiel and on top of dash board and see what happend

sounds like a bad eeprom.If thats not it start looking in the power supply.