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V3 MR-372-J84-62B000$110.mif
Vdiag No.: 44
ALP 15 Passenger compartment ventilation noises
NOTESOnly deal with this customer complaint after a full check with the diagnostic tool
(fault reading and configuration checks).
The aim of the following operations is to check and, if necessary, eliminate any foreign bodies
(leaves, insects, other, etc.) in:
–the passenger compartment air inlet,
–the cabin filter housing,
–the housing and on the fan assembly.
Check the passenger compartment air inlet and the cabin filter housing:
Remove:
–the scuttle panel grille (see MR 371 Bodywork, 55A, Exterior equipment, Scuttle panel grille: Removal -
Refitting),
–the air filter access panel,
–the scuttle panel partition,
–the cabin filter.
Check that there are no foreign bodies (leaves, insects, other, etc.) and, if necessary, clean the passenger
compartment air inlet and the cabin filter housing.
Refit:
–the cabin filter,
–the scuttle panel partition,
–the air filter access panel,
the scuttle panel grille (see MR 371 Bodywork, 55A, Exterior equipment, Scuttle panel grille: Removal -
Refitting).
Check the housing and the fan assembly:
Remove the fan assembly (see MR 370 Mechanical, 61A, Heating, Fan assembly: Removal - Refitting).
Check that there are no foreign bodies (leaves, insects, other, etc.) and, if necessary, clean the fan assembly
housing.
Check that there are no foreign bodies (leaves, insects, other, etc.) and, if necessary, clean the fan assembly.
Refit the fan assembly (see MR 370 Mechanical, 61A, Heating, Fan assembly: Removal - Refitting).
AFTER REPAIRPerform a complete check using the diagnostic tool.
ACREG X84 1.1
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Vdiag No.: 44
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MEASURING THE CONTROL VOLTAGE OF THE PASSENGER COMPARTMENT BLOWER
POWER MODULE
There are two ways to measure the control voltage of the passenger compartment blower power module:
1 / MEASURING USING
A MULTIMETER (in the voltmeter position, direct voltage measurement):
With the power module connector connected, measure across track 6 of the module and the earth.
At speed 0 the voltage measured is equal to the battery voltage (± 1 V) and at speed 8 the voltage is 5 V (± 0.5 V). The
voltage varies between 0 and 14 V for the seven intermediate speeds.
Examples of measurements taken with the voltmeter with the engine at idling speed (values given as a guide):
2 / MEASURING USING
AN OSCILLOSCOPE (Optima 5800, CLIP technique):
The blower power module is controlled by pulse width modulated control voltage (PWM).
This control voltage is always 12 V, it is the control signal (square signal) that varies:
the amplitude and frequency do not vary but instead the high status (12 V) varies in relation to the low status (5 V).
To take the measurement, connect the earth lead of the oscilloscope to the battery earth and the measuring lead of the
oscilloscope to track 6 (6-track connector) of the power module (module connector connected).
Adjust the time base on the oscilloscope to 500 µµ µ µ
s per division with a calibration of 5 V per division.
The signals obtained should be: a straight line at 14 V (± 1 V) for speed 0, and a straight line at 5 V (± 0.5 V) for speed 8.
Examples of measurements taken with the oscilloscope with the engine at idling speed (for information only):
* Passenger compartment blower PWM: passenger compartment blower pulse width modulation control voltage.
Passenger
compartment
blower speed012345678
Voltage
measurement13.77 V 12.26 V 11.79 V 11.22 V 10.43 V 9.44 V 8.08 V 6.66 V 4.96 V
PR019
Passenger
compartment
blower PWM
setting*0% 18% 23% 30% 39% 51% 66% 82% 100%
Passenger
compartment
blower speed012345678
Duration of high
status....... 450 µs400 µs350 µs300 µs250 µs200 µs150 µs.......
Duration of low
status....... 50 µs100 µs150 µs200 µs250 µs300 µs350 µs.......
PR019
Passenger
compartment
blower PWM
setting*0% 18% 23% 30% 39% 51% 66% 82% 100%
ACREG X84 1.1
Edition 2
MR-372-J84-62B000$120.mif
62B - 59
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Vdiag No.: 44
Electrical specifications of the temperature sensors according to temperature
(tolerance: ± 5%).
Interior temperature sensor
Temperature Sensor resistance Temperature Sensor resistance
- 30 ˚C 175200 Ω25
°° ° °
C10000 ΩΩ Ω Ω
- 25 ˚C 129300 Ω26 ˚C 9574 Ω
- 20 ˚C 96360 Ω27 ˚C 9168 Ω
- 15 ˚C 72500 Ω28 ˚C 8783 Ω
- 10 ˚C 55050 Ω29 ˚C 8416 Ω
- 5 ˚C 42160 Ω30 ˚C 8059 Ω
0 ˚C 32560 Ω35 ˚C 6535 Ω
5 ˚C 25340 Ω40 ˚C 5330 Ω
10 ˚C 19870 Ω45 ˚C 4372 Ω
15 ˚C 15700 Ω50 ˚C 3606 Ω
16 ˚C 14991 Ω55 ˚C 2989 Ω
17 ˚C 14318 Ω60 ˚C 2490 Ω
18 ˚C 13679 Ω
19 ˚C 13074 Ω
20 ˚C 12490 Ω
21 ˚C 11942 Ω
22 ˚C 11422 Ω
23 ˚C 10928 Ω
24 ˚C 10458 Ω
ACREG X84 1.1
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Vdiag No.: 44
Operation of the engine cooling fan assembly according to the refrigerant fluid pressure
and vehicle speed.
GMV = 1 Engine cooling fan low speed
GMV = 2 Engine cooling fan high speed
GMV = 0 Engine cooling fan stopped
The engine cooling fan assembly is not used for vehicle speeds over 42 mph (70 km/h), except in rare cases where
the refrigerant fluid pressure is above 23 bar in spite of the speed (e.g.: driving behind a lorry).
When stationary, the engine cooling fan is used systematically at low speed if the refrigerant fluid relative pressure is
below 19 bar, at high speed in the opposite case.
While driving, the engine cooling fan may either not operate, or operate at low or high speed depending on the
refrigerant fluid pressure at the condenser outlet and the vehicle speed.Pressure (relative bar)
AIR CONDITIONING DEACTIVATION
GMV = 2
GMV = 2 GMV = 1 GMV = 0
GMV = 1 GMV = 0
GMV = 1 GMV = 0
AIR CONDITIONING DEACTIVATION
12 (20) 18 (30) 27 (45) 42 (70) Vehicle speed in
mph (km/h)
ACREG X84 1.1
Edition 2
