23 · Diagnostics

Climate control air flow irregular

Make: Alfa Romeo
Model: 159 Factory Service Manual
Year: 2005–2011
Section: Climate control › Climate control air flow irregular

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Fault diagnosisClimate control air flow irregular

CLIMATE CONTROL AIR FLOW IRREGULAR

Automatic Air Conditioning

The flow of air sent by the fan in the passenger compartment using the manual speed control is not sufficient; it does not correspond to the speed set.

0	PRELIMINARY CHECKS	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Connect the Examiner diagnostic equipment and check the following at the Body Computer Node: - that the Logistic Mode is deactivated (with this function activated there is a limit on the passenger compartment heater fan speed)	Move on to Step 1	Logistic Mode function activated.	Deactivate the Logistic Mode function.
1	BATTERY CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Disconnect the battery and reconnect it with the Key Off and wait for 2 minutes for the Key On checking whether there is a variation in the air flow rate.	End of diagnosis	There is no variation in the air flow rate.	Move on to Step 2
2	CHECK ON OPERATION OF FAN BY CLIMATE CONTROL SYSTEM CONTROL UNIT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	With the engine started, set the climate control system control unit to the AUTO position, adjust the temperature to 22°C, place the recirculation at the outside air intake and the distribution to the front position. Adjust the fan button (+ side) gradually increasing the speed set and then decrease the speed using the button (- side), thereby checking the effect of the air flow rate variation.	End of diagnosis	There is no variation in the air flow rate.	Move on to Step 3
3	CHECK USING DIAGNOSTIC EQUIPMENT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Connect the Examiner diagnostic equipment and check the following at the Climate Control Node: that there are no errors at the passenger compartment fan; that there are no errors at the distribution actuators; that there are no errors linked to the fan (short circuit errors).	Move on to Step 4	1. Error at the passenger compartment fan.	1. Move on to Step 7
			2. Short circuit to earth error at the distribution actuators.	2. Check that the Lin Bus cables are not caught between the metal parts (pay special attention to the gearbox bolts) and move on to Step 7.
			3. Short circuit to error to +12V at the distribution actuators.	3. Check that the Lin Bus cables are not caught between the metal parts (pay special attention to the gearbox bolts) and move on to Step 7.
			4. Mechanical lock error / interference at the distribution actuators.	4. Move on to Step 9
			5. Short circuit error at the passenger compartment fan.	5. Move on to Step 7
4	CHECKS USING DIAGNOSTIC EQUIPMENT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Keeping the Examiner diagnostic equipment connected, check the following through active diagnosis: - the correct operation of the air distribution actuators	Move on to Step 5	Air distribution actuator not working.	Move on to Step 6.
5	CHECK ON AIR DUCTS AND POLLEN FILTER	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check that the air ducts are intact and the vents are not blocked and are correctly positioned in the opening. Check that the pollen filter is not obstucted.	Move on to Step 5	1. Air ducts or vents obstructed.	1. Restore the operation of the air ducts and the vents removing any material causing an obstruction.
		Move on to Step 5	2. Pollen filter blocked.	2. Replace the pollen filter Op. 5010B09 PURIFYING (POLLEN) FILTER FILTER ELEMENT - REPLACE
6	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 distribution actuators of the climate control system control unit connector See E6020 AIR CONDITIONING	Move on to Step 7	1. Electrical connections loose or damaged.	1. Renew the electrical connections.
		Move on to Step 7	2. Electrical connection broken or not insulated.	2. Restore the continuity/insulation of the electrical connection.
7	CHECK ON ELECTRICAL CONNECTIONS AND FAN OPERATION	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check whether the electrical wiring connections are loose. Disconnect/reconnect the connection to the engine mounting. Disconnect the connector and connect to a feeder. In these conditions the motor should rotate at the maximum speed indicating that the operating module is not working	Move on to Step 8	1.Electrical connections loose.	1.Renew the correct connections See E6020 AIR CONDITIONING
			2.The fan does not work.	2.Replace the fan Op. 5040C30 AIR CONDITIONING FAN - R.R.
			3.The operating module does not work.	3.Replace the fan operating module Op. 5040C40
8	CHECK ON CORRECT OPERATION OF DISTRIBUTION ACTUATOR	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check whether the electrical wiring connections are loose. Disconnect and visually inspect for damage at the connector contacts and reconnect the connection to the motor mounting. If it persists, before replacing the actuator, check its operation by manually activating the function that the actuator should carry out. With the engine running, switch on the fan at maximum speed. Place the flaps in the various distribution positions via the control/control unit (manually). Check the air flow in the passenger compartment with your hand at the vents.	End of diagnosis	1. Electrical connections loose or damaged.	1. Renew the electrical connections See E6020 AIR CONDITIONING
		End of diagnosis	2. There is no air flow intake into the passenger compartment through the vents.	2. Move on to Step 9.
9	CHECK FOR IMPEDIMENTS TO THE ROTATION OF THE DISTIRUBTION ACTUATOR	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Remove the actuator and check using the control unit control that the actuator turns checking for mechanical impediments to its rotation.	End of diagnosis	1.The actuator does not turn.	1.Replace the timing actuator Op. 5040D63 AIR DISTRIBUTION FLAP CONTROL ACTUATORS- R.R. WITH AIR CONDITIONING CASING REMOVED
		End of diagnosis	2.Kinematic components or flaps broken/stuck	2.Replace the components that is faulty.

Manual Air Conditioning

The flow of air sent by the fan in the passenger compartment using the manual speed control is not sufficient; it does not correspond to the speed set.

0	PRELIMINARY CHECKS	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Disconnect the battery and reconnect it with the Key Off and wait for 2 minutes for the Key On checking whether there is a variation in the air flow rate.	End of diagnosis	There is no variation in the air flow rate.	Move on to Step 1
1	AIR DUCTS CHECK	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check that the air ducts are intact and the vents are not blocked and are correctly positioned in the opening.	Move on to Step 2	1.Air ducts or vents obstructed	1.Restore the operation of the air ducts and the vents removing any material causing an obstruction.
		Move on to Step 2	2.The flow of air does not correspond to the distribution selected.	2.Move on to Step 8.
2	CHECK ON CORRECT OPERATION OF MAXIMUM SPEED RELAY	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check for loose electrical wiring connections, disconnect visually inspecting for any damage to the connector contacts. Reconnect the connection to the resistor. Check that the fan is working at the maximum speed: if it only works at the maximum speed, the relay is broken. Check whether the resistor is broken by checking the electrical continuity in accordance with the See Test 5040CF Sequential procedure for checking air conditioner fan resistor operation	Move on to Step 3	1.Electrical connections loose or damaged.	1. Renew the electrical connections See E6020 AIR CONDITIONING
			2.Relay broken.	2.Replace the ceramic resistor Op. 5040C48
			3.Resistance values faulty	2.Replace the ceramic resistor Op. 5040C48
3	CHECK USING DIAGNOSTIC EQUIPMENT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Connect the Examiner diagnostic equipment and check the following at the Climate Control Node: - that there are no errors at the distribution actuator	Move on to Step 4	1. Short circuit to earth error	1. Renew the correct electrical connections See E6020 AIR CONDITIONING
			2. Short circuit to +12V error	2. Renew the correct electrical connections See E6020 AIR CONDITIONING
			3. Mechanical interference / stuck error	3. Move on to Step 10.
4	CHECKS USING DIAGNOSTIC EQUIPMENT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Keeping the Examiner diagnostic equipment connected, check the following through active diagnosis: - the correct operation of the air distribution actuator	Move on to Step 6	Air distribution actuator not working.	Move on to Step 5.
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 distribution actuators of the climate control system control unit connector See E6020 AIR CONDITIONING	Move on to Step 6	1. Electrical connections loose or damaged.	1. Renew the electrical connections.
		Move on to Step 6	2. Electrical connection broken or not insulated.	2. Restore the continuity/insulation of the electrical connection.
6	CHECK ON CORRECT OPERATION OF SPEED SELECTOR AT THE CLIMATE CONTROL SYSTEM CONTROL UNIT	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check for loose electrical wiring connections, disconnect visually inspecting for any damage to the connector contacts. Reconnect the connection to the selector at the climate control system control unit. Check whether the selector on the control unit is interrupted by checking the electrical continuity in accordance with the See Test 5040DF Sequential procedure for checking air conditioner fan operation	Move on to Step 7	1.Electrical connections loose or damaged.	1. Renew the electrical connections See E6020 AIR CONDITIONING
			2.Fan not working.	2.Replace the speed selector knob Op. 5040D23
			3.Power supply to the relays not correct.	3.Replace the climate control system control unit Op. 5040D17
7	CHECK ON CORRECT OPERATION OF FAN	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check whether the electrical wiring connections are loose. See E6020 AIR CONDITIONING Disconnect, visually inspecting for any damage to the connector contacts. Reconnect the connection to the engine mounting. Check that it rotates at all speeds by activating it using the switch. If it does not rotate at maximum speed, check the fan maximum speed relay See J041	Move on to Step 8	1.Electrical connections loose or damaged	1. Renew the electrical connections See E6020 AIR CONDITIONING
		Move on to Step 8	2. Electric fan	2.Replace the fan Op. 5040C30 AIR CONDITIONING FAN - R.R.
8	CHECK ON CORRECT OPERATION OF FAN MAXIMUM SPEED OPERATING RELAYS	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check whether the electrical wiring connections are loose. Disconnect, visually inspecting for any damage to the connector contacts. Reconnect the connection to the relay. Check that the relay is working properly by providing it with a direct 12 V supply.	Move on to Step 9.	1.Electrical connections loose or damaged	1. Renew the electrical connections See E6020 AIR CONDITIONING
		Move on to Step 9.	2.Maximum speed operating relay not working.	2.Replace the maximum speed operating relay Op. 5040C48
9	CHECK ON CORRECT OPERATION OF DISTRIBUTION ACTUATOR	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Check whether the electrical wiring connections are loose. Disconnect and visually inspect for damage at the connector contacts and reconnect the connection to the motor mounting. If it persists, before replacing the actuator, check its operation by manually activating the function that the actuator should carry out. With the engine running, switch on the fan at maximum speed. Place the flaps in the various distribution positions via the control/control unit. Check the air flow in the passenger compartment with your hand at the vents.	End of diagnosis	1. Electrical connections loose or damaged.	1. Renew the electrical connections See E6020 AIR CONDITIONING
		End of diagnosis	2. There is no air flow intake into the passenger compartment through the vents.	2. Move on to Step 10
10	CHECK FOR IMPEDIMENTS TO THE ROTATION OF THE DISTIRUBTION ACTUATOR	ALL OK	PROBLEMS ENCOUNTERED	ACTION
	Remove the actuator and check using the control unit control that the actuator turns checking for mechanical impediments to its rotation.	End of diagnosis	1.The actuator does not turn.	1.Replace the timing actuator Op. 5040D63
		End of diagnosis	2.Kinematic components or flaps broken/stuck	2.Replace the components that is faulty.

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