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Home >> Ford >> 2018 >> Mustang EcoBoost, 2D Convertible, Standard Trans >> Repair and Diagnosis (Single Page) >> Heating, Ventilation & A/C (HVAC) >> HVAC Control Systems >> Climate Control System - General Information (2 Of 2) >> Diagnosis And Testing >> Climate Control System - Vehicles With: Electronic Manual Temperature Control (EMTC) >> Symptom Chart(s) >> Symptom Chart: Climate Control - Electronic Manual Temperature Control (EMTC)
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Symptom Chart: Climate Control - Electronic Manual Temperature Control (EMTC)

Diagnostics in this article assume a certain skill level and knowledge of Ford-specific diagnostic practices. REFER to: Diagnostic Methods .

Condition Possible Sources Actions
A module does not communicate with the diagnostic scan tool Fuse(s)
Wiring, terminals or connectors
REFER to: Communications Network .
Externally Controlled Variable Displacement Compressor (EVDC) poor performance/does not operate correctly Refer to Pinpoint Test GO to Pinpoint Test N 
Unable To Duplicate The Customer Concern And No Diagnostic Trouble Codes (DTCs) Present Refer to Pinpoint Test GO to Pinpoint Test C 
Reduced outlet airflow Plugged cabin air filter INSPECT the cabin air filter. REFER to: Cabin Air Filter . If OK, DIAGNOSE for low refrigerant charge, A/C always commanded on or blower motor not operating correctly.
Improper refrigerant level CARRY OUT the refrigerant system tests. REFER to: Refrigerant System Tests - 2.3L EcoBoost (231kW/314PS) . REFER to: Refrigerant System Tests - 5.0L 32V Ti-VCT . REFER to: Refrigerant System Tests - 5.2L 32V Ti-VCT . If refrigerant charge is OK, GO to Pinpoint Test H 
Blower motor GO to Pinpoint Test K 
The air inlet door is inoperative Refer to Pinpoint Test GO to Pinpoint Test D 
Incorrect or erratic direction of airflow from outlets Refer to Pinpoint Test GO to Pinpoint Test E 
Insufficient, erratic or no heat Refer to Pinpoint Test GO to Pinpoint Test F 
The A/C is inoperative Refer to Pinpoint Test GO to Pinpoint Test G 
The A/C is always on -- A/C mode always commanded ON Refer to Pinpoint Test GO to Pinpoint Test H 
Temperature control is inoperative/does not operate correctly Refer to Pinpoint Test GO to Pinpoint Test I 
The blower motor is inoperative Refer to Pinpoint Test GO to Pinpoint Test J 
The blower motor does not operate correctly Refer to Pinpoint Test GO to Pinpoint Test K 
Insufficient A/C cooling Improper refrigerant level CARRY OUT the refrigerant system tests. REFER to: Refrigerant System Tests - 2.3L EcoBoost (231kW/314PS) . REFER to: Refrigerant System Tests - 5.0L 32V Ti-VCT . REFER to: Refrigerant System Tests - 5.2L 32V Ti-VCT . If OK, DIAGNOSE for a temperature door actuator not operating correctly.
Temperature door actuator GO to Pinpoint Test I 
A/C pressure relief valve discharging A/C pressure relief valve CHECK the high side system pressure. If the pressure is below the A/C pressure relief valve open pressure, 3, 447-4, 137 kPa (500-600 psi), INSTALL a new A/C pressure relief valve. Refer to the appropriate Climate Control Systems article for the procedure.
High system pressure CHECK the high side system pressure. If the system pressure is above the A/C pressure relief valve open pressure, 3, 447-4, 137 kPa (500-600 psi), REPAIR the A/C system for a restriction.
Climate control does not operate only when remote start is used IPC information display settings
Non-Ford approved remote start system installed
VERIFY Remote Start - Message Center Set To Auto, or Remote Start - Message Center Set To Last User Settings. REFER to: Climate Control System - Vehicles With: Electronic Manual Temperature Control (EMTC) - System Operation and Component Description .
VERIFY module communications network operation. DIAGNOSE Diagnostic Trouble Codes (DTCs) if present.