1997 MERCEDES-BENZ ML350 light

AR88.40-P-3200GH
Removing and installing engine hood lock
8.4.99

MODEL
163.136 /154 /172 up to 31.8.99

P88.40-2054-06

1
Screw

2
Bottom section of engine hood lock

3
Engine hood control cable mount

4
Screw

5
Upper section of engine hood lock with

safety hook


Removal, installation

1
Open engine hood and position upright
Up to 08.99

AR88.40-P-1000GH

As of 09.99

AR88.40-P-1000GI

2
Unscrew screws (1) and remove upper

section of engine hood lock (2) upward

*BA88.40-P-1003-01C

3
Remove release lever on inside of vehicle

and unhook engine hood cable from lever

4
Unhook engine hood cable from bottom
section of engine hood lock (2)


Pull engine hood cable out slightly. Press

holder (3) on engine hood cable carefully off

engine hood lock.

5
Remove bottom section of engine hood lock (2)


Installation:
Ensure that engine hood

cable is routed carefully.

6
Unscrew screws (4) and remove upper

section of engine hood lock (5)

Mark installation position of upper section

of engine hood lock on engine hood.


*BA88.40-P-1004-01C

7
Install in opposite order

8
Lubricate engine hood lock

e

AP88.40-P-8821GH

9
Check for proper function

10
Check safety hook for proper function

For this purpose, close engine hood,

release and check arrest on radiator cross

member

11
Check engine hood fit
If necessary
#

Adjust engine hood

AR88.40-P-3020GH

Engine hood

Number

Designation
Model 163

BA88.40-P-1003-01C
Screw for engine hook lock on radiator cross

member
Nm
12

BA88.40-P-1004-01C
Screw for engine hood lock upper section on

engine hood
Nm
12

Copyright DaimlerChrysler AG 09.05.2006 CD-Ausgabe G/10/04 . This WIS print-out will not be recorde
d by Modification services.
Page 1

Fig. 2: Locating Climate Control Components
Courtesy of MERCEDES-BENZ OF NORTH AMERICA
FRESH/RECIRCULATION SWITCH
Fresh/recirculation switch controls voltage signal to fresh air recirculation door motor. See Fig. 1 and Fig. 2 .
With switch indicator light on, air will recirculate. With switch indicator light off, air will enter from outside of
vehicle.
A/C CONTROL MODULE
The A/C control module (A/C amplifier) is the control unit for the A/C system. See Fig. 2 . The module
receives inputs from various sensors and processes the information to control various outputs for the A/C
system for optimal control.
The A/C control module inputs are as follows:
A/C Switch
In-Vehicle Air Temperature Sensor
Temperature Selector Knob
Blower Motor Knob
Evaporator Temperature Sensor
Air Mix Damper Door Position Sensor
The A/C control module output functions are as follows:
Air Mix Damper Door Motor
All Activity Module
Fresh/Recirculation Door Motor
ALL ACTIVITY MODULE
All Activity Module (AAM) receives inputs to determine if specified conditions have been met to allow
operation of A/C-heater system. If conditions are met, the AAM will send signals to the A/C compressor,
condenser fans relay and the blower motor relay to command or enable operation.
IN-VEHICLE TEMPERATURE SENSOR
The in-vehicle temperature sensor is a negative temperature coefficient resistor. Sensor sends signals to the A/C
control module to maintain in-vehicle temperature. Sensor is located on the center panel of the instrument
cluster.
DUST FILTER
A dust filter provides filtering of air entering or recirculating in the passenger's compartment. The dust filter is
mounted between blower motor and evaporator, below passen
ger's side of instrument panel, to left of blower

2001 Mercedes-Benz ML320
2000-01 MANUAL A/C-HEATER SYSTEMS ML 320, ML 430 & ML 55
me
Saturday, October 02, 2010 3:25:10 PMPage 5 © 2006 Mitchell Repair Information Company, LLC.

FUNCTIONAL TEST PREPARATION
1. Check condition of fuses F16, F41, F43 and F44. See WIRING DIAGRAMS . Repair and/or replace
fuses and necessary.
2. Turn ignition on. Locate in-vehicle temperature sensor aspirator blower vent grille above anti-theft
indicator light. Place a half-inch square of tissue paper over aspirator blower vent grille. If paper stays on
vent grille, go to next step. If paper does not stay on vent grille, correct insufficient aspirator blower
ventilation.
3. Put shift lever in "P" and engage parking brake. Run engine at idle until it reaches normal operating
temperature, about 176°F (80°C). Ensure ambient (outside) temperature is greater than 58°F (15°C).
4. Manually open center and side air outlets. Ensure recirculation button is not depressed. Set blower speed
knob to position No. 1.
FUNCTION TEST
Defrost Mode
To check operation in defrost mode, set temperature selector knob to White range (vertical). Set mode control
knob to 12-o'clock position (vertical). Ensure A/C button indicator is illuminated. Air will vent from defrost and
center outlets and A/C compressor will engage. If operation is not as specified, perform the following in order:
Check voltage supply circuit Z50/2 between No. 16 fuse (15-amp) and connected components. See
VOLTAGE SUPPLY CIRCUIT Z50/2
under ELECTRICAL TESTS.
Check ground circuit. See GROUND CIRCUIT Z50/4 under ELECTRICAL TESTS.
Check in-vehicle temperature sensor signal voltage. See IN-VEHICLE TEMPERATURE SENSOR
under ELECTRICAL TESTS.
Check in-vehicle temperature sensor signal resistance. See IN-VEHICLE TEMPERATURE SENSOR
under ELECTRICAL TESTS.
Check icing protection temperature sensor signal voltage. See ICING PROTECTION
TEMPERATURE SENSOR under ELECTRICAL TESTS.
Check icing protection temperature sensor resistance. See ICING PROTECTION TEMPERATURE
SENSOR under ELECTRICAL TESTS.
Check activation voltage during temperature reduction. See ACTIVATION VOLTAGE
TEMPERATURE under ELECTRICAL TESTS.
Check activation voltage during temperature increase. See ACTIVATION VOLTAGE
TEMPERATURE under ELECTRICAL TESTS.
Check blend air flap actuator motor operation voltage. See BLEND AIR FLAP ACTUATOR MOTOR
under ELECTRICAL TESTS.
Check blend air flap actuator motor resistance. See BLEND AIR FLAP ACTUATOR MOTOR under
ELECTRICAL TESTS.
Check A/C button activation. See A/C BUTTON under ELECTRICAL TESTS.
Check A/C pressure switch. See A/C REFRIGERANT PRESSURE SWITCH under ELECTRICAL NOTE: Function test steps must be performed in order given.

2001 Mercedes-Benz ML320
2000-01 MANUAL A/C-HEATER SYSTEMS ML 320, ML 430 & ML 55
me
Saturday, October 02, 2010 3:25:10 PMPage 9 © 2006 Mitchell Repair Information Company, LLC.

Fig. 6: Removing Cooling Fans & Condenser
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
COOLING FANS
Removal & Installation
Remove headlight units. Remove upper frame crossmember, release hood release control cable and remove
crossmember. See Fig. 6
. Remove 2 cooling fans frame bolts on radiator. Disconnect cooling fan connector.
Release outside temperature sensor wiring harness. Pull up on cooling fan and remove. To install, reverse
removal procedure. Ensure cooling fan bottom guides are properly seated in lower mounts.
EVAPORATOR
Removal & Installation
Remove A/C housing unit. See A/C HOUSING UNIT . Remove expansion valve. See Fig. 5 . Discard "O"
rings. Disassemble A/C housing unit. Remove evaporator. Remove evaporator temperature sensor. To install,
reverse removal procedure. Use NEW "O" rings lubricated with refrigerant oil. If installing a new or repair
evaporator, add 1.35 ounces of NEW refrigerant oil to evaporator.
EXPANSION VALVE
Removal & Installation
1. Discharge A/C system, using approved refrigerant recovery/recycling equipment. Without disconnecting
coolant hoses, remove coolant expansion reservoir and set aside. Remove refrigerant line bracket and
loosen clamps. See Fig. 5
. Pull refrigerant lines out of expansion valve.
2. Remove expansion valve self-locking nut and discard. Remove expansion valve. Discard "O" rings. To
install, reverse removal procedure. Use NEW "O" rings lubricated with refrigerant oil. Tighten NEW self-
locking nut to specification. See TORQUE SPECIFICATIONS
.
INSTRUMENT PANEL & INSTRUMENT PANEL CARRIER
Removal & Installation
1. Secure vehicle against rolling. Set transmission selector to "D" position. Obtain radio security code.
Disconnect negative battery cable. Remove driver-side air bag.
2. Place match marks on steering wheel and steering shaft. Remove steering wheel, upper steering column
covers and combination switch. Remove instrument cluster cover frame. Remove one instrument panel
lower section bolt.
3. Remove screws in footwell from left side of instrument panel bottom section. Remove instrument panel
center section. Remove 4 A/C control panel screws and remove control panel. See Fig. 1
. Release pull
cables and disconnect connectors.
4. Remove screws from center section. Remove glove box. Remove screws in footwell from right side of
instrument panel bottom section. Remove entry courtesy lights. Remove end covers and screws.
5. Release 4 "A" clips between instrument panel bottom section and upper section. See Fig. 7
. Release
parkin
g brake release cable from handle. With assistance, remove instrument panel bottom section.

2001 Mercedes-Benz ML320
2000-01 MANUAL A/C-HEATER SYSTEMS ML 320, ML 430 & ML 55
me
Saturday, October 02, 2010 3:25:10 PMPage 21 © 2006 Mitchell Repair Information Company, LLC.

Fig. 9: Replacing Intake Air Dust Filter
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
RECEIVER-DRIER
Removal & Installation
1. Discharge A/C system, using approved refrigerant recovery/recycling equipment. Remove headlight
units. Remove headlight units. Remove upper frame crossmember, release hood release control cable and
remove crossmember. See Fig. 6
.
2. Remove bolts from receiver-drier refrigerant lines. See Fig. 5
. Disconnect refrigerant lines from receiver-
drier. Plug exposed openings to protect A/C system from debris and moisture. Discard "O" rings. Loosen
receiver-drier clamp bolt. Remove receiver-drier. To install, reverse removal procedure.
3. When installing a new receiver-drier, add 0.34 ounce of NEW refrigerant oil to receiver-drier. Use NEW
"O" rings. Tighten refrigerant line bolts to specification. See TORQUE SPECIFICATIONS
.
TORQUE SPECIFICATIONS
TORQUE SPECIFICATIONS
WIRING DIAGRAMS
ApplicationFt. Lbs. (N.m)
Compressor Mounting Bolts15 (20)
Refrigerant Line-To-Compressor Bolt15 (20)
Refrigerant Line-To-Condenser Bolt15 (20)
Steering Column Bolt15 (20)
Steering Column Nut13 (18)
INCH Lbs. (N.m)
Expansion Valve Self-Locking Nut89 (10)
Refrigerant Line-To-Receiver-Drier Bolt89 (10)

2001 Mercedes-Benz ML320
2000-01 MANUAL A/C-HEATER SYSTEMS ML 320, ML 430 & ML 55
me
Saturday, October 02, 2010 3:25:10 PMPage 25 © 2006 Mitchell Repair Information Company, LLC.

The in-car temperature sensor (B10/4) is equipped with an aspirator blower which constantly draws air out of
the vehicle interior for the temperature measurement when the ignition is ON . The in-car temperature sensor
(B10/4) records the interior temperature and conveys it to the AAC push-button control module. A comparison
is made there with the setting on the temperature selector and the blend air flap is repositioned depending on the
result of this comparison.
It is connected to the AAC push-button control module via a separate electric cable.
Constant circulation of the interior air at the in-car temperature sensor (B10/4) is achieved by the in-car
temperature sensor aspirator blower (M9) and therefore ensures a high level of control accuracy.
In contrast to the previous suction jet nozzle a high level of control accuracy is ensured by the in-car
temperature sensor aspirator blower (M9).
OUTSIDE AIR TEMPERATURE SENSOR FUNCTION - GF83.57-P-2103-01GH
Function
The resistance of the outside air temperature sensor (B10/5) depends on the ambient temperature and the ground
speed. With an increase in the outside temperature, its resistance decreases. This information is sent to the air
conditioning control module (N19). This information causes a slight lowering or raising of the temperature
selected at the air conditioning control panel.
This achieves an adaptation to the temperature perception of the occupants.
The outside temperature depends on the ground speed, which prevents a value for the outside temperature that is
too high - as may occur when the vehicle is stationary or when traveling slowly, e.g. due to thermal radiation
from the engine - from being sent to the air conditioning control module (N19).
The value of the ground speed is sent from the traction systems control module (N47) via the instrument cluster
(A1) to the air conditioning control module (N19).
When switching the ignition off and on and with speeds lower than 20 km/h the temperature measured last is
used.
OUTSIDE AIR TEMPERATURE SENSOR POSITION - GF83.57-P-2103-02GH
The outside air temperature sensor (B10/5) is located at the front on the air inlet of the evaporator housing.

2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:17 PMPage 141 © 2006 Mitchell Repair Information Company, LLC.

Fig. 128: Identifying Rear Air Stream Temperature Sensor
AMBIENT TEMPERATURE DISPLAY TEMPERATURE SENSOR, FUNCTION - GF83.57-P-2119-01GI
Function
The resistance of the ambient temperature display temperature sensor is dependent on the ambient temperature
and speed. The current resistance value is sent via the CAN data bus to the AAC push-button control module
(N22), which then slightly readjusts the set temperature.
The fact that the ambient temperature is dependent on the speed helps to prevent any excess temperature being
sent to the AAC push-button control module (N22) when the car is at a standstill or traveling slowly, e.g. as
induced b
y engine heat radiation.

Rear air stream
temperature sensor,
locationThe rear air stream temperature sensor (B10/7) is located to the left of the rear
passenger compartment blower motor housing behind the rear nozzle.

Rear air stream
temperature sensor,
taskThe rear air stream temperature sensor (B10/7) records the temperature of the air
flowing in the rear passenger compartment and sends it to the AAC push-button
control module (N22).


Rear air stream
temperature sensor,
functionThe recorded temperature value for the rear ventilation air stream is compared by
the AAC push-button control module (N22) with the setting in the temperature
selector wheel and authorizes a corresponding adjustment to the blending air flap
to be made depending upon the result.


2001 Mercedes-Benz ML320
1998-2005 HVAC Climate Control - 163 Chassis
me
Saturday, October 02, 2010 3:23:17 PMPage 151 © 2006 Mitchell Repair Information Company, LLC.

GF54.30-P-2001A
Indicator / warning displays, function
24.10.96

MODEL
129, 140 as of 1.6.96,

163, 168, 170,

202 as of 1.8.96,

208 up to 31.7.99,

210 as of 1.6.96 up to 30.6.99

The table below lists the various warning alarms and indications

according to type (visual/acoustic) and their actuation (direct/CAN).

Visual warning and indicator signals actuated over direct lines:
D
Left turn signal indicator lamp (A1e1)

D
Right turn signal indicator lamp (A1e2)

D
High beam indicator lamp (A1e3)

D
Fuel reserve warning lamp (A1e4)

D
Brake fluid / parking brake warning lamp (A1e7) (except model

163)

D
Low windshield washer fluid level warning lamp (A1e13) (as of

01.09.01 also valid for model 163)

D
Low engine coolant level warning lamp (A1e11) (except model

168, model 163 as of 3.99)

D
Coolant level and temperature warning lamp (A1e11) (only model

168 as of 9.99 and only coolant level function)

D
Generator charge indicator/warning lamp (A1e5)

D
Seat belt warning lamp (A1e9)

D
Seatbelt/backrest lock warning lamp (A1e9)

D
Exterior lamp failure indicator lamp (A1e14)

-----------------------------------------------------------------------------------------
D

Hydraulic fluid level warning lamp (A1e37)

D
ADS warning lamp, suspension (A1e27)

D
Steering lock warning lamp (A1e40) (only

I
)

D
SRS airbag malfunction indicator lamp (A1e15)

D
AIRBAG OFF indicator lamp (A1e56), only model 163 except

I

Also refer to document: Indicator and warning signals triggered

over CAN data lines
Acoustic warning and indicator signals actuated over direct

lines:
D
Turn signal ticker

D
Seat belt reminder

D
Switched-on lights reminder

D
Key warning

D
Soft top warning, only model 170


Also refer to document: Acoustic warnings, function

Acoustic warning and indicator signals actuated over CAN data

lines:
D
Parking brake warning

D
Vehicle speed warning

D
Vehicle speed limit warning

D
Gear warning, only model 168


Also refer to document: Acoustic warnings, function

Indicator and warning signals triggered over

direct lines

GF54.30-P-3002A

Indicator and warning signals triggered over

CAN data lines

GF54.30-P-3003A
Acoustic warnings, function
GF54.30-P-3010A

Copyright DaimlerChrysler AG 04.06.2006 CD-Ausgabe G/10/04 . This WIS print-out will not be recorde
d by Modification services.
Page 1