Page 43 of 60

62B-43
CLIMATE CONTROL
Fault finding – Fault Finding Chart62B
V3 MR-372-J84-62B000$110.mif
Vdiag No.: 44
CLIMATE CONTROL
Fault finding – Fault Finding Chart
ALP 1 No dialogue with the computer
NOTESNone.
Try the diagnostic tool on another vehicle.
Check:
–the connection between the diagnostic tool and the diagnostic sensor (wiring in good condition),
–the connection between the vehicle's diagnostic sensor and the diagnostic socket (cable in good condition),
–the injection, engine and passenger compartment fuses.
Check for + 12 V battery on track 16, and + 12 V after ignition feed on track 1 and an earth on track 5 and
on track 4 of the diagnostic socket.
Repair if necessary.
Disconnect the connector from the climate control computer in order to check the insulation, continuity and
the absence of interference resistance of the following connections:
Climate control computer 12-track connector:
Track 11 + before ignition (see the vehicle wiring diagram)
Track 10 + accessories feed (see the vehicle wiring diagram)
Track 6 Earth
Track 7 Track 6 of the diagnostic socket (CAN H)
Track 1 Track 14 of the diagnostic socket (CAN L)
Repair if necessary (see the vehicle wiring diagram).
AFTER REPAIRPerform a complete check using the diagnostic tool.
ACREG X84 1.1
Edition 2
Page 50 of 60

62B-50
CLIMATE CONTROL
Fault finding – Fault Finding Chart62B
V3 MR-372-J84-62B000$110.mif
Vdiag No.: 44
ALP 5 No passenger compartment ventilation
NOTESOnly consult this customer complaint after a complete check using the
diagnostic tool.
Special notes:
The 2 x 5-track intermediate connector is located on the LH side of the distribution /
ventilation unit (behind a plastic cover) and the passenger compartment fan control
module is located slightly higher up, below the heater matrix pipes.
Check that the fusesare in good condition.
Using the diagnostic tool, check that the passenger compartment fan
control setting given by the computer varies from 0 to 100% by checking
parameter PR019 Passenger compartment fan PWM setpoint
(refer to the interpretation of this status).
Does the value vary?
YES
Check that the control voltage (PWM) (modulated control voltage) of the passenger
compartment fan power module varies between 5 and 12 V (from 0 to 100%) by
measuring between track 6 of the module's 6-track connector and earth
(connector connected).
Note:
The check procedure is given in the Help section.
Does the voltage vary correctly?
NO
Check the insulation, continuity and absence of interference resistance on the
following connection:
Air conditioning computer 18-track
connector
track 7
Repair if necessary.Power module 6-track connectortrack 6
With the ignition on, check for +12 V accessories feed on track B1 and an earth on track B5
of the black 2 x 5 track intermediate connector (screwed to the base of the console).
Repair if necessary.
NO
YES Contact your
TECHLINE.
AFTER REPAIRPerform a complete check using the diagnostic tool.
ACREG X84 1.1
Edition 2
Page 54 of 60

62B-54
CLIMATE CONTROL
Fault finding – Fault Finding Chart62B
V3 MR-372-J84-62B000$110.mif
Vdiag No.: 44
ALP 13 No control panel lighting
NOTESOnly refer to this customer complaint after a full check of the multiplex network
and the air conditioning with the fault finding tool.
Special notes:
With the ignition on, the control panel screen is permanently on but the panel buttons
only light up when the sidelights are switched on.
Note:
If the external temperature sensor is faulty, the climate control computer is
switched on 5 seconds after the ignition is switched on (this allows a fault to be
identified as fault finding cannot be performed on the external temperature sensor
by the UCH).
Is the fault common to other components (instrument panel,
multifunction display, electric window buttons, etc.)?
YES
Switch on the ignition and switch on the side lights to check
there is a 12 V supply on track 6 of the brown 12-track
connector (PPH2) of the Protection and Switching Unit.
Is there a 12 V supply?
YES
Check the connection and the condition of the connectors at the air conditioning control panel
output.
Repair if necessary.
Check the insulation, continuity and absence of interference resistance on the following
connection:
Air conditioning computer 12-track connector
track 9
Repair if necessary.Protection and Switching Unit brown 12-track
(PPH2) connector
track 6
NO
NOPerform fault finding on the
protection and switching unit.
AFTER REPAIRPerform a complete check using the diagnostic tool.
ACREG X84 1.1
Edition 2