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Symptom Chart - Climate Control Systems

WARNING: This page is about a different car, the 2015 Lincoln MKS. However, it is still accessible from the selected car via links, so may be relevant.

Diagnostics in this article assume a certain skill level and knowledge of Ford-specific diagnostic practices. Refer to Diagnostic Methods in Service Information for information about these practices.

Condition Possible Sources Action
NOTE: Some PCM DTCs may inhibit A/C operation. If any PCM DTCs are retrieved, diagnose those first. Refer to the PCM DTC Chart .
No communication with the HVAC module Fuse(s)
Wiring, terminals or connectors
Communication network
HVAC module
REFER to Module Communications Network .
Externally Controlled Variable Displacement Compressor (EVDC) poor performance/does not operate correctly Refer to the Diagnostic Routine GO to Pinpoint Test U .
Unable to duplicate the customer concern and no DTCs present Refer to the Diagnostic Routine GO to Pinpoint Test H .
HVAC functions are inoperative/do not operate correctly from touchscreen only Communication network
FCDIM
For 8 inch (203mm) Touch Screen, 10 Speakers, REFER to Information and Entertainment Systems - 8-Inch (203 mm) Touchscreen, 10 Speakers and DIAGNOSE the touchscreen.
For THX, 8 Inch (203mm) Touch Screen, 14 Speakers, REFER to Information and Entertainment Systems - THX® 8-Inch (203 mm) Touchscreen, 16 Speakers and DIAGNOSE the touchscreen.
HVAC functions are inoperative/do not operate correctly from steering wheel switches/infotainment display only Steering wheel switches
Clockspring
SCCM
IPC
For 8 inch (203mm) Touch Screen, 10 Speakers, REFER to Information and Entertainment Systems - 8-Inch (203 mm) Touchscreen, 10 Speakers and DIAGNOSE the steering wheel switches.
For THX, 8 Inch (203mm) Touch Screen, 14 Speakers, REFER to Information and Entertainment Systems - THX® 8-Inch (203 mm) Touchscreen, 16 Speakers and DIAGNOSE the steering wheel switches.
Reduced outlet airflow Refer to the Diagnostic Routine If the A/C compressor does not cycle, GO to Pinpoint Test M .
If the A/C compressor cycles normally, GO to Pinpoint Test R .
The air inlet door is inoperative Refer to the Diagnostic Routine GO to Pinpoint Test I .
Incorrect/erratic direction of airflow from outlets Refer to the Diagnostic Routine GO to Pinpoint Test J .
Insufficient, erratic or no heat Refer to the Diagnostic Routine GO to Pinpoint Test K .
The air conditioning (A/C) is inoperative Refer to the Diagnostic Routine GO to Pinpoint Test L .
The air conditioning (A/C) is always on - A/C compressor does not cycle Refer to the Diagnostic Routine GO to Pinpoint Test M .
The air conditioning (A/C) is always on - A/C mode always commanded ON Refer to the Diagnostic Routine GO to Pinpoint Test N .
Temperature control is inoperative/does not operate correctly - LH Refer to the Diagnostic Routine GO to Pinpoint Test O .
Temperature control is inoperative/does not operate correctly - RH Refer to the Diagnostic Routine GO to Pinpoint Test P .
The blower motor is inoperative Refer to the Diagnostic Routine GO to Pinpoint Test Q .
The blower motor does not operate correctly Refer to the Diagnostic Routine GO to Pinpoint Test R .
A/C pressure relief valve discharging High system pressure
A/C pressure relief valve
CHECK the high side system pressure. If the pressure is below the A/C pressure relief valve open pressure, INSTALL a new A/C compressor. REFER to Climate Control . TEST the system for normal operation. If the system pressure is above the A/C pressure relief valve open pressure, REPAIR the system for a restriction.