Pinpoint Test H : The A/C (Air Conditioning) Is Always On - A/C (Air Conditioning) Mode Always Commanded On

WARNING: This page is about a different car, the 2017 Ford Edge. However, it is still accessible from the selected car via links, so may be relevant.

NOTE: Use the correct probe adapter(s) when making measurements. Failure to use the correct probe adapter(s) may damage the connector.

H1 CHECK THE A/C (AIR CONDITIONING) CLUTCH RELAY
- Carry out the component test on the A/C clutch relay. Refer to OEM WIRING DIAGRAMS COMPONENT TESTING for schematic and connector information.
Did the relay pass the component test?

Yes GO to H2

No INSTALL a new A/C clutch relay.

H2 CHECK THE A/C (AIR CONDITIONING) COMPRESSOR CLUTCH FIELD COIL VOLTAGE SUPPLY CIRCUIT FOR A SHORT TO VOLTAGE

Ignition OFF.

Disconnect A/C compressor clutch field coil C100 .

Disconnect the A/C clutch relay.

Ignition ON.

Measure:

Positive Lead	Measurement / Action	Negative Lead
C100-1	Courtesy of FORD MOTOR COMPANY	Ground

Is any voltage present?

Yes	REPAIR the circuit.

No	GO to H3

H3 COMPARE THE EVAPORATOR TEMPERATURE SENSOR TO THE PCM (POWERTRAIN CONTROL MODULE) AMBIENT AIR TEMPERATURE (AAT) PID (PARAMETER IDENTIFICATION)

Ignition OFF.

Allow the vehicle exterior and interior to stabilize to ambient temperature.

Disconnect Evaporator Temperature Sensor C296 .

Measure:

Positive Lead	Measurement / Action	Negative Lead
C296-1 (component side)	Courtesy of FORD MOTOR COMPANY	C296-2 (component side)

Compare the resistance values to the table below:

Ambient Temperature °F (°C)	Approximate Resistance
-4.0°F (-20°C)	13.820 K ohms - 14.283 K ohms
32.0°F (°C)	4.790 K ohms - 4.915 K ohms
68.0°F (20°C)	1.830 K ohms - 1.900 K ohms
77.0°F (25°C)	1.475 K ohms - 1.530 K ohms
103.9°F (40°C)	790 - 825 ohms
139.9°F (60°C)	370 - 390 ohms

Ignition ON.

Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).

Monitor the AAT PID.

Are the temperature values similar?

Yes

GO to H4

No	INSTALL a new evaporator temperature sensor. REFER to: Evaporator Temperature Sensor .

H4 CHECK THE FCIM (FRONT CONTROLS INTERFACE MODULE) A/C (AIR CONDITIONING) SWITCH STATUS (CC_SW_AC) PID (PARAMETER IDENTIFICATION)
- Ignition ON.
- Using a diagnostic scan tool, view FCIM Parameter Identifications (PIDs).
- Monitor the CC_SW_AC PID.
- Select panel mode, press and release the A/C button (indicator off) on the FCIM controls.
Does the PID display Active when pressed and Inactive when released?

Yes GO to H5

No GO to H8

H5 CHECK THE PCM (POWERTRAIN CONTROL MODULE) (A/C) PRESSURE SENSOR (ACP_PRESS) PID (PARAMETER IDENTIFICATION)
- Using a diagnostic scan tool, view the PCM Parameter Identification (PIDs).
- With a manifold gauge set connected, compare the pressure readings of the manifold gauge set and the PCM Parameter Identification (PID) ACP_PRESS.
Are the pressure values of the manifold gauge set and the ACP_PRESS PCM PID within ± 15 psi (103 kPa)?

Yes GO to H6

No INSTALL a new A/C pressure transducer. REFER to: Air Conditioning (A/C) Pressure Transducer .

H6 CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) REQUEST SIGNAL (AC_REQ) PID (PARAMETER IDENTIFICATION) WITH THE A/C (AIR CONDITIONING) OFF
- Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
- Monitor the AC_REQ PID.
- While in panel mode, release the A/C button (indicator off) on the FCIM controls.
Does the PID display off?

Yes GO to H9

No GO to H7

H7 CHECK THE PCM (POWERTRAIN CONTROL MODULE) A/C (AIR CONDITIONING) REQUEST SIGNAL (AC_REQ) PID (PARAMETER IDENTIFICATION) WITH FCIM (FRONT CONTROLS INTERFACE MODULE) DISCONNECTED
- Ignition OFF.
- Disconnect FCIM C2402A .
- Ignition ON.
- Using a diagnostic scan tool, view PCM Parameter Identifications (PIDs).
- Monitor the AC_REQ PID.
Does the PID display off?

Yes GO to H9

No GO to H8

H8 CHECK FOR CORRECT FCIM (FRONT CONTROLS INTERFACE MODULE) OPERATION

Ignition OFF.

Disconnect and inspect all FCIM connectors.

Repair:
- corrosion (install new connector or terminals - clean module pins)
- damaged or bent pins - install new terminals/pins
- pushed-out pins - install new pins as necessary

Connect all FCIM connectors. Make sure they seat and latch correctly.

Operate the system and determine if the concern is still present.

Is the concern still present?

Yes

CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new FCIM. For vehicles equipped with Sony® Audio System, REFER to: Front Controls Interface Module (FCIM) . For vehicles equipped with Touchscreen Display, REFER to: Front Controls Interface Module (FCIM) . For all other audio systems, REFER to: Front Controls Interface Module (FCIM) .

No	The system is operating correctly at this time. The concern may have been caused by a loose or corroded connector. ADDRESS the root cause of any connector or pin issues.

H9 CHECK FOR CORRECT PCM (POWERTRAIN CONTROL MODULE) OPERATION

Ignition OFF.

Disconnect and inspect all PCM connectors.

Repair:
- corrosion (replace connector or terminals - clean module pins)
- damaged or bent pins - replace terminals/pins
- pushed-out pins - replace pins as necessary

Connect all PCM connectors. Make sure they seat and latch correctly.

Operate the system and verify the concern is still present.

Is the concern still present?

Yes

CHECK OASIS for any applicable Technical Service Bulletins (TSBs). If a TSB exists for this concern, DISCONTINUE this test and FOLLOW TSB instructions. If no Technical Service Bulletins (TSBs) address this concern, INSTALL a new PCM. Refer to POWERTRAIN CONTROL MODULE (PCM) - 2.0L EcoBoost (184kW/250PS) - MI4. REFER to: POWERTRAIN CONTROL MODULE (PCM) - 2.7L EcoBoost (238kW/324PS). REFER to: POWERTRAIN CONTROL MODULE (PCM) - 3.5L Duratec (212kW/278PS).

No	The system is operating correctly at this time. The concern may have been caused by module connections. ADDRESS the root cause of any connector or pin issues.