Document Information

Location: Powertrain Systems - HVAC

Topic: Set temperature not achieved or incorrect air/vent distribution
Condition: Intermittent and/or permanent

Diagnostic Trouble Codes: N/A

Measure

This procedure can be applied to calibrate the HVAC system in the event of a
customer complaint for HVAC performance issues and/or intermittent ‘CAL’ message
displayed.

Care Point: The HVAC air filter housing also includes the fresh air re-circulation
flap/motor. It is not uncommon that during maintenance of the HVAC air filter it is
refitted in a position where it can restrict the movement of the re-circulation flap
which in turn causes various HVAC operation concerns. Ensure this area is checked
first.

Care Point: To ensure the HVAC calibration is successfully completed, save HVAC
actual values in .pdf before and after the calibration procedure, Review and compare
the minimum and maximum individual HVAC motor values to confirm that there has
been a change. Depending on the initial position of the motors, the change in values
may only be minimal but it shows that they have responded to the calibration
sequence,

There are two different HVAC calibration procedures based on the model:
= All Sports Series vehicles, 720S (Coupe & Spider), Senna, New GT
1. Turn the ignition ON

2. Unplug one of the HVAC motors (whichever is easier to access). Refer to the
attachment area of this KA to identify the locations of the motors

3. Cycle through the following A/C settings for at least 60 seconds. During this
operation the error message message “Climate Control Fault" will be displayed on the
driver's display

a) Air distribution buttons (5)

b) Recirc button (10)

c) Temperature control (left and right) (7, 12)

4, Then, connect the MDS and ensure there is at least one DTC stored for the
disconnected motor. If no DTCis present, repeat Step 3 and this time cycle through
the settings for longer time

5, Adjust the fan to minimum speed (do not turn it OFF), this will enable you to hear
the flap motors calibrating when the ignition is turned ON at step 8

6. Turn the ignition OFF and allow the vehicle to go into sleep
7. Re-connect the motor that was disconnected at step 2
8. Turn the ignition ON

9, At this stage, the HVAC system will start calibrating and you should be able to hear
all the motors moving during this time. Allow approximately 3-4 minutes for the
calibration to complete

10. Once the calibration is finished (no message is displayed to confirm calibration is
finished), check operation of the HVAC system

11. If the HVAC is operating as designed, delete all the DTCs and return the vehicle to
the customer

= 12C (Coupe & Spider), 625C, 650S (Coupe & Spider), 675LT (Coupe & Spider),
Pl

1. Turn the ignition ON
2. Turn the HVAC ON

3. Disconnect one of the motors (whichever is easier to access). Refer to the
attachment area of this KA to identify the locations of the motors.

4, Re-connect the motor that was disconnected
5. The message ‘CAL’ will be displayed, and the system will start calibrating
6, Once the calibration is completed, check operation of the HVAC system

7. If the HVAC is operating as designed, delete all the DTCs and return the vehicle to
the customer

Parts Information

N/A

Warranty Information
Resolution Category

Casual Part Number: N/A

Casual Part Name: N/A

Casual Issue: N/A

Rectification: N/A

Time: N/A