Page 3273 of 4133
REAR FOOTWELL AIR OUTLET, LOCATION/TASK/FUNCTION - GF83.10-P-2146GI
MODEL 163 as of 1.9.01 with CODE (580a) Automatic air conditioning
Fig. 24: Identifying Left And Right Rear Compartment Air Vent
CENTER NOZZLE, LOCATION/PURPOSE/FUNCTION - GF83.10-P-2149GC
MODEL 163, 168
Rear footwell air vent taskThe rear footwell air vent is used to ventilate the rear
footwell.
Rear footwell air vent
function GF83.10-P-2110-
01GC
Rear footwell air vent
locationThe left and right rear footwell air vents (1,2) are below the
passenger and driver's seats.
Rear footwell air vent
taskThe left and right rear footwell air vents (1,2) are used to
ventilate the rear footwell.
Rear footwell air vent
function GF83.10-P-2110-
01GI
Center nozzle,
locationModel 168GF83.10-P-
2107-02GC
GF83.10-P-
2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:15 PMPage 29 © 2006 Mitchell Repair Information Company, LLC.
Page 3274 of 4133
SIDE NOZZLE, LOCATION/PURPOSE/FUNCTION - GF83.10-P-2150GC
MODEL 163, 168
REAR COMPARTMENT NOZZLE LOCATION/TASK/FUNCTION - GF83.10-P-2151GI
MODEL 163 as of 1.9.01 with CODE (580a) Automatic air conditioning
Model 1632107-02GH
Center nozzle,
purposeThe center nozzle serves for specific guidance and distribution of the
air in the upper section of the front vehicle passenger compartment.
Center nozzle,
functionModel 168GF83.10-P-
2107-01GC
Model 163GF83.10-P-
2107-01GH
Side nozzle,
locationModel 168GF83.10-P-
2108-02GC
Model 163GF83.10-P-
2108-02GH
Side nozzle,
purposeThe left and right side nozzles serve for specific guidance and
distribution of the air in the passenger compartment on the driver and
passenger sides.
Side nozzle,
functionModel 168GF83.10-P-
2108-01GC
Model 163GF83.10-P-
2108-01GH
2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:15 PMPage 30 © 2006 Mitchell Repair Information Company, LLC.
Page 3275 of 4133
Fig. 25: Identifying Rear Nozzle
SERIES RESISTOR GROUP, LOCATION/TASK/FUNCTION - GF83.10-P-2161GC
MODEL 163 up to 31.8.01, 168
Rear nozzle
positionThe rear nozzle (1) is located at the rear center console.
Rear nozzle
taskThe rear compartment nozzle provides specific rear compartment
ventilation in addition to the rear footwell air vents.
Rear nozzle
function GF83.10-P-
2111-01GI
Series resistor group,
positionModel 168GF83.10-P-2124-
01GC
Model 163GF83.10-P-2124-
01GH
Series resistor
assembly taskThe series resistor assembly controls the blower voltage
depending on the relevant blower level setting.
Series resistor
assembly functionModel 168 up to 28.02.01GF83.10-P-2124-
02GC
Model 168 as of 01.03.01GF83.10-P-2124-
02GH
Model 163GF83.10-P-2124-
2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:15 PMPage 31 © 2006 Mitchell Repair Information Company, LLC.
Page 3276 of 4133

REAR BLOWER MOTOR, FU NCTION - GF83.10-P-2168-01GI
Function
The rear blower motor (M2/1) is actuated using the bl ower button ( ) on the rear ventilation control panel
(N72/2s3).
Pressing the blower button ( ) passes a control voltage to the rear blower motor (M2/1) via the electronic
rear ventilation blower regulat or (N29/2). This facilitates blower speed control of 0-100 %.
Automatic mode function
Pressing the Auto button ( ) on the rear ventilation control panel (N72/2s3) causes the rear blower motor to
be regulated by the AAC push- button control module (N22).
REAR BLOWER MOTOR, PO SITION/TASK/DESIGN/FUNCTION - GF83.10-P-2168GI
MODEL 163 as of 1.9.01 with CODE (580a) Automatic air conditioning
Fig. 26: Identifying Rear Blower Motor
02GD
Blower,
locationThe rear blower motor (M2/1) is located behind the rear nozzle below
the center console.
2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
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Page 3277 of 4133

BLOWER MOTOR FUNCTION - GF83.10-P-2170-01GI
Function
The AAC push-button control module (N22) passes a control voltage of 0-6 V to the blower regulator (A32n1)
via the AC bus. Depending on the control voltage which is present, this then regulates the blower motor
(A32m1) operating voltage of 0-12 V. This facilitates blower speed control of 0-100 %.
The blower motor actuation (operating voltage) is influenced by the following factors:
Blower power setting manual or AUTO
Operating functions:
Air distribution
AC OFF mode
Residual engine heat mode (actuation limited to 5 V)
Mode status (heating, cooling)
Coolant temperature
Vehicle speed
Fresh air/recirculation flap setting
Flap positions
Terminal 15 (blower ON), starter running (blower OFF)
BLOWER MOTOR LOCATION/TASK/DESIGN/FUNCTION - GF83.10-P-2170GI
MODEL 163 as of 1.9.01 with CODE (580a) Automatic air conditioning
Blower, task
The rear blower motor (M2/1) serves to improve ventilation and cooling
in the rear.
The air that is drawn in by the blower in the evaporator housing is led to
the rear blower motor (M2/1) via air ducts.
The rear blower motor (M2/1) increases the flow of air.
Blower,
function GF83.10-P-
2168-01GI
2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:15 PMPage 33 © 2006 Mitchell Repair Information Company, LLC.
Page 3278 of 4133

Fig. 27: Identifying Blower Motor
REAR SHUTOFF FLAP ACTUATOR MOTOR FUNCTION - GF83.10-P-2171-01GI
Function
Pressing the rear compartment air distribution button ( ) on the AAC push-button control module (N22)
actuates the rear shutoff flap actuator motor (M12/2) via the AC bus. The rear shutoff flap actuator motor
(M12/2) therefore controls the rear shutoff flap, which opens and controls the air supply to the rear blowout
ducts.
Blower
motor
locationThe blower motor (A32m1) is to the bottom right of the evaporator housing
below the glove compartment.
Blower
motor task
In fresh air mode the blower motor draws in fresh air via the fresh
air/recirculating air flap. In recirculating air mode, air from the vehicle interior
is drawn into the evaporator housing via the fresh air/recirculating air flap.
When residual engine heat utilization is being used, the blower motor circulates
the air around the interior.
Blower
motor
design
The blower motor is designed as a radial blower.
Blower
motor
function
GF83.10-P-
2170-01GI
2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:15 PMPage 34 © 2006 Mitchell Repair Information Company, LLC.
Page 3279 of 4133

If a problem exists, it is possible to retrieve and verify the defined end positions by means of the diagnosis
assistant system (DAS) (valuation trip).
After replacing an actuator motor an adjustment run must be performed via the Diagnosis Assistant System
(DAS), i.e. the end positions flap OPEN and SHUT are defined and retained.
REAR SHUTOFF FLAP ACTUATOR MOTOR LOCATION/TASK/FUNCTION - GF83.10-P-2171GI
MODEL 163 as of 1.9.01 with CODE (580a) Automatic air conditioning
Fig. 28: Identifying Rear Shutoff Flap Actuator Motor
CENTER OUTLET FLAP ACTUATOR MOTOR - GF83.10-P-2172-01GI
NOTE: All actuator motors are identical.
Rear shutoff flap
actuator motor
locationThe rear shutoff flap actuator motor (M2/12) is to the left of the
automatic air conditioning housing.
Rear shutoff flap
actuator motor taskThe rear shutoff flap actuator motor (M2/12) operates the rear
shutoff flap for controlling the flow of air to the rear
compartment nozzle.
Rear shutoff flap
actuator motor
function
GF83.10-P-
2171-01GI
2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:15 PMPage 35 © 2006 Mitchell Repair Information Company, LLC.
Page 3280 of 4133

Function
Rotating the air distribution switch in the AAC push-
button control module (N22) actuates the center outlet flap
actuator motor (M2/22) via the AC bus. The center outlet flap actuator motor (M2/22) controls the center outlet
flap, which adopts the following positions according to requirements.
Switching logic
center outlet flap closed = 0%
center outlet flap open = 100%
Automatic center outlet flap control (Auto button engaged)
The center outlet flap is opened depending on the following values
blending air flap setting
Coolant temperature
Evaporator temperature
linear up to 100 % open.
Center outlet flap control via push-button control module (Clock type switch setting of air distribution
switch)
If a problem exists, it is possible to retrieve and verify the defined end positions by means of the diagnosis
assistant system (DAS) (valuation trip).
After replacing an actuator motor an adjustment run must be performed using the Diagnosis Assistant System
(DAS), i.e. the flap OPEN and SHUT limit positions are defined and retained.
CENTER OUTLET FLAP ACTUATOR MOTOR, LOCATION/TASK/FUNCTION - GF83.10-P-2172GI
MODEL 163 as of 1.9.01 with CODE (580a) Automatic air conditioning
1 o'clock 2 o'clock 3 o'clock 4 o'clock 5 o'clock6 o'clock
65% 82% 100% 68% 2%
0%
7 o'clock 8 o'clock 9 o'clock 10 o'clock 11 o'clock
12 o'clock
32% 68% 100% 82% 65%
50%
NOTE: All actuator motors are identical.
2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:15 PMPage 36 © 2006 Mitchell Repair Information Company, LLC.