Then get it scanned as one of the potentiometers may be screwed up do this test to see if you get any dtc's then if not have it scanned.
Ensure coolant temperature is at least 120 F (49 C) before entering self-diagnostics. Ensure in-car temperature is between 40-90 F (4-32 C). Simultaneously depress OFF and FLOOR buttons, then press AUTOMATIC button within 2 seconds. Display will show a dashed line in the center of the display window for up to 30 seconds while test is running. Record all DTCs as displayed.
If DTCs are displayed, perform test indicated. See DTC INDEX table. If a condition exists but no DTCs are displayed, go to SYMPTOM TESTS.
Self-diagnostics can be initiated at any time with the resulting DTCs being displayed. Normal system operation is stopped when system is in self-diagnostic mode.
If this has a water valve on the car and it might but we never are shown that, see if hoses stay hot at higher rpm. That is vacuum operated and maybe be screwed up it used to be on eof the big things causeing heat problems on ford products. Here are dtc's and what failure is.
B1249 024 (022)Blend Door Actuator Short
B1249 N/A (025)Blend Door Actuator Failure
B1251 031 (N/A)In-Car Temp. Sensor Open
B1253 030 (N/A)In-Car Temp. Sensor Short
B1255 041 (043)Ambient Air Temp. Sensor Open
B1257 040 (042)Ambient Air Temp. Sensor Short
B1261 050 (052)Sunload Temp. Sensor Short
U1073 (2) N/A (N/A)Engine Coolant Temp. Signal
U1341 (2) N/A (N/A)Vehicle Speed Sensor
might also be a broken blend door shaft as these are known to happen as well. Also the heater care cold be plugged, so try back flushing it, may help.
Tuesday, November 3rd, 2020 AT 10:59 AM