22 · Diagnostics

Climate control not cooling

Make: Fiat
Model: Croma Factory Service Manual
Year: 2005–2010
Section: Climate control › Climate control not cooling

‹ Prev Fan does not work at different speeds Next › Climate control does not cool to the desired temperature

Fault diagnosisClimate control not cooling

CLIMATE CONTROL NOT COOLING

The fan works properly and sends air to the passenger compartment according to the pre-set flows but the air remains at the outside temperature and is not cooled.

MANUAL AIR CONDITIONING

0	PRELIMINARY CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Connect the climate control systme to the special repressurizing equipment and check the pressure of the system See Test 5040OB CHECK ON OPERATION OF AIR CONDITIONING SYSTEM (PRESSURE) Check the correct operation of the engine cooling fan	Move on to Step 4	1.Pressure not correct	1.Move on to Step 1.
		Move on to Step 4	2.Incorrect operation of the engine cooling fan	2.Carry out the test. See Test 5040AB REFRIGERANT CIRCUIT CHECK
1	CHECK FOR GAS LEAKS FROM CONDENSER	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	With the engine started, the climate control system on (compressor ON button), using the leak detector check that the leak is by the system pipes housing or the housing for the drier filter of the pipe joins at the condenser pack.	Move on to Step 2	1.Gas leak from condenser.	1.Replace the condenser and refill correctly. Op. 5040A40 AIR CONDITIONING CONDENSER - R+R
		Move on to Step 2	2.O-ring puckered.	2.Replace the o-rings and refill correctly. Op. 0010T84 COOLANT FOR AIR CONDITIONING SYSTEM - DEHYDRATE AND REPRESSURIZE Mark the point where the gas is escaping on the condenser.
2	CHECK FOR GAS LEAKS FROM EVAPORATOR	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	With the engine started, the climate control system on (compressor ON button), use the leak detector to check that the leak is from the expansion valve or by the bend in the pipes	Move on to Step 3	1.Gas leak from condenser.	1.Replace the evaprator and refill correctly. Op. 5040C64 A/C EVAPORATOR - R+R
		Move on to Step 3	2.O-ring puckered.	2.Replace the o-rings and refill correctly. Op. 0010T84 COOLANT FOR AIR CONDITIONING SYSTEM - DEHYDRATE AND REPRESSURIZE Mark the point where the gas is escaping on the condenser.
3	CHECK FOR GAS LEAKS FROM COMPRESSOR	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	With the engine started, the climate control system at the maximum speed (compressor ON button), place the temperature adjustment knob/button in the maximum cold position, move the "nose" of the leak detector near the connector to be analyzed and check for any leaks. If the result is positive (leak), repeat the test to make sure that there really is a leak. With the engine switched off, move the "nose" of the leak detector near the area of the compressor shaft and the area of the compressor rear gasket. If the result is positive (leak), repeat the test to make sure that there really is a leak.	Move on to Step 4	1.O-ring puckered.	1.Replace the o-rings and refill correctly. Op. 0010T84 COOLANT FOR AIR CONDITIONING SYSTEM - DEHYDRATE AND REPRESSURIZE
			2.Leak from compressor shaft.	2.Replace the compressor Op. 5040A20 AIR CONDITIONING COMPRESSOR - R+R - INCLUDES FLUID LEVEL CHECK AND TOP UP IF NECESSARY
			3.Leak from compressor rear gasket.	3.Replace the compressor Op. 5040A20 AIR CONDITIONING COMPRESSOR - R+R - INCLUDES FLUID LEVEL CHECK AND TOP UP IF NECESSARY
4	CHECK USING DIAGNOSTIC EQUIPMENT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Connect the Examiner diagnostic equipment and check that there are no errors at the linear sensor.	Move on to Step 5	Error at the linear sensor	Move on to Step 8
5	CHECK USING DIAGNOSTIC EQUIPMENT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Keeping the diagnostic equipment connected, check: that there are no errors at the engine management node; through active diagnosis, that the compressor engagement relay is working correctly, making sure that, at the same time, the compressor electromagnet coupling is activated.	Move on to Step 8	1.Error at Engine Management Node.	1.Continue as instructed by the diagnostic equipment
			2.The relay comes on and the coupling is not activated.	2.Move on to Step 6
			3.The relay comes on and the coupling is not activated.	3.Move on to Step 7
6	ELECTRICAL CIRCUIT CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the continuity/insulation of the electrical circuit for the compressor engagement relay See E6021 COMPRESSOR ENGAGEMENT	Move on to Step 8	1.Electrical connections interrupted or not insulated.	1.Restore continuity/insulation for electrical connections See E6021 COMPRESSOR ENGAGEMENT
		Move on to Step 8	2.Compressor engagement relay faulty	2.Replace the compressor engagement relay
7	ELECTRICAL CIRCUIT CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the continuity/insulation of the electrical power circuit for the compressor See E6021 COMPRESSOR ENGAGEMENT	Move on to Step 8	1.Electrical connections interrupted or not insulated.	1.Restore continuity/insulation for electrical connections See E6021 COMPRESSOR ENGAGEMENT
		Move on to Step 8	2.Electromagnet coupling faulty.	2.Replace the compressor complete with coupling Op. 5040A20 AIR CONDITIONING COMPRESSOR - R+R - INCLUDES FLUID LEVEL CHECK AND TOP UP IF NECESSARY
8	COMPRESSOR ENGAGEMENT CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check that the compressor comes on correctly by carrying out the test. See Test 5040BC CHECK ON ENGAGEMENT/DISENGAGEMENT OF COMPRESSOR THROUGH LINEAR SENSOR	Move on to Step 9	1.Electrical connections broken.	1.Check and, if necessary, restore the continuity/insulation for the electrical connection See E6021 COMPRESSOR ENGAGEMENT
		Move on to Step 9	2.Linear sensor does not give the go ahead.	2.Replace the linear sensor Op. 5040B20 AIR CONDITIONING LINEAR PRESSURE TRANSDUCER - R.R.
9	CHECK ON CORRECT OPERATION OF MIXTURE ACTUATOR KINEMATIC MECHANISM	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Visually inspect aht the mixture actuator is working properly from the temperature control knob for the climate control system. Check whether the control at the control unit is broken by measuring the electrical continuity through the test. See Test 5040DH SEQUENTIAL PROCEDURE FOR CHECKING OPERATION OF MIXTURE AND DISTRIBUTION ACTUATORS	End of diagnosis	1.Incorrect operation of actuator	1.Replace the mixture actuator See Test
		End of diagnosis	2. Physical impediment to flap rotation	2. Replace the control unit.
			3.Incorrect operation of the control actuator on the climate control unit	3.Replace the climate control system control unit See Test 5040D17 CONTROL UNIT WITH MANUAL AIR CONDITIONER KNOBS AND BUTTONS R R

AUTOMATIC AIR CONDITIONING

The fan works properly and sends air to the passenger compartment according to the pre-set flows but the air remains at the outside temperature and is not cooled.

The enablement of the engagement of the refrigeration circuit is controlled by both the climate control node and the engine management node

0	PRELIMINARY CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Connect the climate control systme to the special repressurizing equipment and check the pressure of the system See Test 5040OB CHECK ON OPERATION OF AIR CONDITIONING SYSTEM (PRESSURE) Check the correct operation of the engine cooling fan.	Move on to Step 4	1.Pressure not correct	1.Move on to Step 1
		Move on to Step 4	2.Incorrect operation of the engine cooling fan.	2.Carry out the test See Test 5040AB REFRIGERANT CIRCUIT CHECK
1	CHECK FOR GAS LEAKS FROM CONDENSER	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	With the engine started, the climate control system on (compressor ON button), using the leak detector check that the leak is by the system pipes housing or the housing for the drier filter of the pipe joins at the condenser pack.	Move on to Step 2	1.Gas leak from condenser.	1.Replace the condenser and refill correctly. Op. 5040A40 AIR CONDITIONING CONDENSER - R+R
		Move on to Step 2	2.O-ring puckered.	2.Replace the o-rings and refill correctly. Op. 0010T84 COOLANT FOR AIR CONDITIONING SYSTEM - DEHYDRATE AND REPRESSURIZE Mark the point where the gas is escaping on the condenser.
2	CHECK FOR GAS LEAKS FROM EVAPORATOR	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	With the engine started, the climate control system on (compressor ON button), use the leak detector to check that the leak is from the expansion valve or by the bend in the pipes	Move on to Step 3	1.Gas leak from condenser.	1.Replace the evaprator and refill correctly. Op. 5040C64 A/C EVAPORATOR - R+R
		Move on to Step 3	2.O-ring puckered.	2.Replace the o-rings and refill correctly. Op. 0010T84 COOLANT FOR AIR CONDITIONING SYSTEM - DEHYDRATE AND REPRESSURIZE Mark the point where the gas is escaping on the condenser.
3	CHECK FOR GAS LEAKS FROM COMPRESSOR	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	With the engine started, the climate control system at the maximum speed (compressor ON button), place the temperature adjustment button in the LO, move the "nose" of the leak detector near the pipe outlet connector and check for any leaks. If the result is positive (leak), repeat the test to make sure that there really is a leak. With the engine switched off, move the "nose" of the leak detector near the area of the compressor shaft and the area of the compressor rear gasket. If the result is positive (leak) repeat the test to make sure that there really is a leak.	Move on to Step 4	1.O-ring puckered.	1.Replace the o-rings and refill correctly. Op. 0010T84 COOLANT FOR AIR CONDITIONING SYSTEM - DEHYDRATE AND REPRESSURIZE
			2.Leak from compressor shaft.	2.Replace the compressor Op. 5040A20 AIR CONDITIONING COMPRESSOR - R+R - INCLUDES FLUID LEVEL CHECK AND TOP UP IF NECESSARY
			3.Leak from compressor rear gasket.	3.Replace the compressor Op. 5040A20 AIR CONDITIONING COMPRESSOR - R+R - INCLUDES FLUID LEVEL CHECK AND TOP UP IF NECESSARY
4	CHECK USING DIAGNOSTIC EQUIPMENT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Connect the diagnostic equipment and check: that there are no errors at the air mixing actuators; that there are no errors at the treated air sensors; that there are no errors at the outside temperature sensor; that there are no errors at the passenger compartment temperature sensor; that there are no errors at the linear sensor.	Move on to Step 6	1.Error at the air mixture actuators.	1.Move on to Step 5
			2.Error at the treated air sensors	2.Move on to Step 5
			3.Error at the outside temperature sensor	3.Move on to Step 5
			4.Error at the passenger compartment temperature sensor	4.Move on to Step 5
			5.Error at the linear sensor.	5.Move on to Step 9
5	ELECTRICAL CIRCUIT CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the continuity/insulation and visually inspect for any looseness or damage at the electrical connection contacts: of the air mixture actuator(s) in the case of an error at the mixture actuator; of the sensor if there is an error at the outside temperature sensor; of the climate control system control unit connector. See E6020 AIR CONDITIONING	Move on to Step 10	1.Electrical connections loose or damaged.	1. Renew the electrical connections See E6020 AIR CONDITIONING
		Move on to Step 10	2.Electrical connection broken or not insulated.	2. Restore the continuity/insulation of the electrical connection See E6020 AIR CONDITIONING
6	PIPE AND FILTER CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check that the air conditioning system high and low pressure pipes are not obstructed.	Move on to Step 7	1.Pipe from compressor to condenser obstructed.	1.Replace pipe from compressor to condenser.obstructed. Op. 5040A40 AIR CONDITIONING CONDENSER - R+R
		Move on to Step 7	2.Pipe from condenser to expansion valve obstructed.	2.Replace pipe from condenser to expansion valve.
7	CHECK USING DIAGNOSTIC EQUIPMENT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Keeping the diagnostic equipment connected, check: that there are no errors at the engine management node; through active diagnosis, that the compressor engagement relay is working correctly, making sure that, at the same time, the compressor electromagnet coupling is activated. correct operation of solar sensor See Test 5040DC CHECK ON OPERATION OF SOLAR SENSOR	Move on to Step 10	1.Errors at Engine Management Node.	1. Continue as instructed by the diagnostic equipment
			2.The relay comes on and the coupling is not activated.	2.Move on to Step 8
			3.The relay comes on and the coupling is not activated.	3.Move on to Step 9
			4.Solar sensor defective.	4.Replace the solar sensor See Test 5010D56 SOLAR SENSOR - R.R FOLLOWING ELECTRICAL SYSTEM CHECK
8	ELECTRICAL CIRCUIT CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the continuity/insulation of the electrical circuit for the compressor engagement relay. See E6021 COMPRESSOR ENGAGEMENT	Move on to Step 10	1.Electrical connections interrupted or not insulated.	1.Restore continuity/insulation for electrical connections See E6021 COMPRESSOR ENGAGEMENT
		Move on to Step 10	2.Compressor engagement relay faulty.	2.Replace the compressor engagement relay
9	ELECTRICAL CIRCUIT CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check the continuity/insulation of the electrical circuit for the compressor engagement relay. See E6021 COMPRESSOR ENGAGEMENT	Move on to Step 10	1.Electrical connections interrupted or not insulated.	1.Restore continuity/insulation for electrical connections See E6021 COMPRESSOR ENGAGEMENT
		Move on to Step 10	2.Electromagnet coupling faulty.	2.Replace the compressor complete with coupling Op. 5040A20 AIR CONDITIONING COMPRESSOR - R+R - INCLUDES FLUID LEVEL CHECK AND TOP UP IF NECESSARY
10	COMPRESSOR ENGAGEMENT CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check that the compressor comes on correctly by carrying out the test See Test 5040BC CHECK ON ENGAGEMENT/DISENGAGEMENT OF COMPRESSOR THROUGH LINEAR SENSOR	Move on to Step 11	1.Electrical connections broken.	1.Check and, if necessary, restore the continuity/insulation for the electrical connection See E6021 COMPRESSOR ENGAGEMENT
		Move on to Step 11	2.Linear sensor does not give the go ahead.	2.Replace the linear sensor Op. 5040B20 AIR CONDITIONING LINEAR PRESSURE TRANSDUCER - R.R.
11	CHECK ON CORRECT OPERATION USING DIAGNOSTIC EQUIPMENT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check that the following errors do not persist: at the air mixture actuators (after a self-learning procedure); at the outside temperature sensor; at the passenger compartment temperature sensor; at the treated air sensors.	End of diagnosis	1.Error at the left air mixture actuators.	1.Move on to Step 12
			2.Error at the right air mixture actuators.	2.Move on to Step 12
			3.Error at the outside temperature sensor.	3.Replace the outside temperature sensor Op. 5010D12 OUTSIDE AIR TEMPERATURE SENSOR ON DOOR MIRROR - R+R FOLLOWING ELECTRICAL CIRCUIT CHECK
			4.Error at the passenger compartment temperature sensor.	4.Replace the climate control system control unit Op. 5010D12 OUTSIDE AIR TEMPERATURE SENSOR ON DOOR MIRROR - R+R FOLLOWING ELECTRICAL CIRCUIT CHECK
			5.Error at the treated air sensors.	5.Replace the treated air sensors.
12	CHECK FOR IMPEDIMENTS TO THE ROTATION OF THE MIXTURE ACTUATORS	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Remove the actuator and check using the control unit control that the actuator turns checking for mechanical impediments that prevent its rotation.	End of diagnosis	1.The actuator does not turn.	1.Replace the mixture actuator Op.
		End of diagnosis	2.Kinematic components of flaps broken/stuck.	2.Replace the faulty component

‹ Prev Fan does not work at different speeds Next › Climate control does not cool to the desired temperature

Parts & tools for this job For 2005 Fiat Croma

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