1997 MERCEDES-BENZ ML320 engine

Fig. 1: Drive Belt Routing
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
TROUBLE SHOOTING
PRELIMINARY INSPECTION
Verify customer complaint by operating system. Visually inspect for obvious signs of mechanical and electrical
damage. Check generator belt tension and condition. Ensure that battery voltage is within specifications. Inspect
for blown fuses and damaged relays.
Verify ground connection integrity between engine, body, battery and generator. Check for damaged wiring
harnesses and/or switches. Check for a broken or partially broken wire inside insulation, which could cause
system malfunction but prove good in a continuity/voltage check with system disconnected. Ensure any
aftermarket electronic equipment is properly installed. If fault is found, repair as necessary. If no fault is found,
check for conditions that might cause an intermittent situation.
SERVICE PRECAUTIONS
BATTERY DISCONNECT/CONNECT
Disconnect Procedures
1. On vehicles not equipped with TELE AID, go to step 5 . Vehicles equipped with TELE AID, switch
TELE AID into service mode by turning ignition ON.
2. Turn ON telephone and enter code "*#4610#" on handset.
3. Confirm that "No Telematics Service" appears on handset with okay.
4. Turn OFF handset.
5. Turn OFF ignition.
6. Open hood and open snap fasteners (1) on dust filter housing. See Fig. 2
.
7. Remove dust filter housing (2) exposing battery.
8. If not using quiescent current retention unit, go to step 14 . If using quiescent current retention unit, go to
next step.
9. Connect quiescent current retention unit by switching on quiescent current retention unit (7) and then first
connecting positive terminal (8) and negative terminal (9) of retention unit to positive cable and battery
ground (W10). See Fig. 3
.
10. On vehicles equipped with TELE AID, remove luggage compartment cargo anchoring lugs and remove
floor paneling.
11. Remove screws (1). See Fig. 4
.
12. Dismantle cover from TELE AID control module (A35/8).
13. Disconnect connection coupling for back up battery and remove back up battery.
14. Disconnect ne
gative battery cable (1) and insulate terminal. See Fig. 5. NOTE: Numbers and letters in text refer to numbers and letters in figures.

2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Generators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:31 PMPage 3 © 2006 Mitchell Repair Information Company, LLC.

3. Normalize side power windows. See NORMALIZING POWER WINDOWS .
4. Start engine and run at idle. Turn steering wheel from one lock position to the other to activate steering
angle sensor. Center steering wheel. Message "EI. STAB. PROGRAM GO TO GARAGE" should erase
from multifunction display panel.
5. If equipped, normalize tilting/sliding roof. See NORMALIZING TILTING/SLIDING ROOF
.
6. If equipped, normalize memory power seats, steering column and outside mirror if components are
installed. See NORMALIZING MEMORY POWER SEATS, STEERING COLUMN & OUTSIDE
MIRROR .
Normalizing Power Windows
1. Completely close each window with manual switch. Hold switch in closed position for .3 second.
2. Repeat procedure for each power window.
Normalizing Memory Power Seats, Steering Column & Outside Mirror
1. Using manual switch, move seat to each end position and hold for .3 second. Repeat procedure for each
switch except rear stop of backrest.
2. Repeat procedure for end positions of steering wheel and outside mirrors.
Normalizing Tilting/Sliding Roof
Open roof with SR switch until mechanical stop is reached. Continue to press switch for .5 seconds.
Setting Time
1. Use bottom left button on steering wheel to scroll through menus on instrument cluster to "Settings"
menu.
2. Move selection marker with + or - button to "Time" submenu.
3. Press up or down arrows to "Clock, hours" setting. Confirm selection marker is on the hour setting.
4. Press + or - to set hour. Press reset knob in instrument cluster to confirm.
5. Move selection marker with + or - button to "Time" submenu.
6. Press up or down arrows to "Clock, minutes" setting. Confirm selection marker is on the minutes setting.
7. Press + or - to set minute. Press reset knob in instrument cluster to confirm.
TESTING
If generator malfunctions, check for Diagnostic Trouble Codes (DTCs) in Motor Electronics Sequential Fuel
Injection (ME-SFI) system. See appropriate SELF-DIAGNOSTICS article in ENGINE PERFORMANCE. If
cause of generator malfunction is not engine performance related, replace generator.
RETRIEVING & ERASING DIAGNOSTIC TROUBLE CODES
NOTE: Before replacing any component that scan tool suggests are faulty, ensure that
all wiring connections and harness connectors are okay. Ensure that power and

2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Generators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:32 PMPage 8 © 2006 Mitchell Repair Information Company, LLC.

RETRIEVING DIAGNOSTIC TROUBLE CODES
To retrieve codes using hand held tester, see Fig. 6 .
Fig. 6: Retrieving Codes Using Hand Held Tester

Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
CLEARING DIAGNOSTIC TROUBLE CODES
Disconnecting vehicle battery will not erase codes. Follow scan tool equipment manufacturers instructions to
erase fault codes.
FAULT CODE DIAGNOSIS EQUIPMENT CONNECTION
To connect hand held tester scan tool to Mercedes-Benz data link connector, see Fig. 7 . To connect hand held
ground circuits are functioning properl
y. For circuit identification, see
appropriate WIRING DIAGRAM unde r ENGINE PERFORMANCE in SYSTEM
WIRING DIAGRAMS for vehicle being tested.
NOTE: For diagnostic equipment conn ections, see FAULT CODE DIAGNOSIS
EQUIPMENT CONNECTION .

2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Gene rators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:32 PMPage 9 © 2006 Mitchell Repair Information Company, LLC.

Fig. 8: Connecting Hand Held Tester Scan Tool To OBD-II Data Link Connector
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
ON-VEHICLE TESTING
WIRING CONTINUITY
1. Connect voltmeter between generator B+ terminal and ground. Voltmeter should indicate battery voltage.
If battery voltage is not indicated, check battery and check wiring between generator and battery for
corrosion, loose terminals, etc.
2. Turn ignition on and ensure instrument cluster charge indicator light (battery symbol) comes on. If light
does not come on, check wiring between generator and warning light, including indicator bulb.
GENERATOR OUTPUT
1. Ensure connections at battery and generator are clean and tight. Ensure generator, engine and body are
properly grounded. Ensure generator drive belt is properly adjusted and in good condition.
2. Connect load tester/ammeter as per tester manufacturer's instructions. Connect voltmeter leads to battery
terminals. See Fig. 9
. Start engine and run at 2200 RPM for V6 or 2500 RPM for V8. Adjust load tester
to obtain maximum generator output. DO NOT allow voltage to drop to less than 12.7 volts.
3. Maximum generator output should be within a few amps of generator rated output stamped on generator.
If output is not within a few amps of generator rated output, check generator diodes. See DIODE TEST
.
Replace
generator as necessary.

2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Generators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:32 PMPage 14 © 2006 Mitchell Repair Information Company, LLC.

VOLTAGE REGULATOR CONTROL
1. Connect multimeter. See Fig. 10 . Ensure charge indicator light goes out when engine is idling and with
increasing engine speed up to 3000 RPM. Apply load to battery by turning on headlights and noting
reading after 2 minutes.
2. Voltage reading should be 13-14.5 volts. If voltage is not to specification, replace voltage regulator. See
VOLTAGE REGULATOR
under REMOVAL & INSTALLATION. If regulator is okay, replace
generator. See GENERATOR under REMOVAL & INSTALLATION.

2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Generators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:32 PMPage 16 © 2006 Mitchell Repair Information Company, LLC.

Connect DC clip-on probe from engine tester with oscilloscope to positive battery terminal. See Fig. 11. Start
engine. Switch on low beam. Access diode test at 3000 RPM. See Fig. 12
-Fig. 14 . Replace generator as
necessar
y.

2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Generators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:32 PMPage 18 © 2006 Mitchell Repair Information Company, LLC.

Fig. 14: Identifying Oscilloscope Patterns (Negative Diode Defective)
Courtesy of MERCEDES-BENZ OF NORTH AMERICA.
REMOVAL & INSTALLATION
GENERATOR
Removal & Installation (Model 163)
Disconnect and shield negative battery cable. Remove air cleaner housing. Remove engine trim panel. Remove
"V" belt b
y swiveling tensioning pulley and holding in place with a drift. Disconnect generator B+ electrical
NOTE: Numbers in text refer to numbers in figures.

2001 Mercedes-Benz ML320
2001-04 STARTING & CHARGING SYSTEMS Generators & Regulators - 163 Chassis
me
Saturday, October 02, 2010 3:20:32 PMPage 22 © 2006 Mitchell Repair Information Company, LLC.

GF54.30-P-2004A
Control buttons, location/task
24.10.96

MODEL
129, 140 as of 1.6.96,

163, 170

The instrument cluster has two control buttons which are on the left
or right next to the speedometer.

The
right control button
is used to adjust the time (refer to Owner's

Manual).

-----------------------------------------------------------------------------------------
The

left control button
is used

D
to regulate the instrument illumination

D
to activate the display illumination

D
to reset the trip odometer display

D
to operate the maintenance display (model 170 only bis 05.97)

D
to operate the Active Service System ASSYST (as of 06.97)

-----------------------------------------------------------------------------------------

n

Purpose/function of terminal 58d, instrument

display illumination
Engines 112, 113, 611 (engines with oil

sensor)

GF54.30-P-3008A

n

Electronic clock
GF54.30-P-3011A

n

Active Service System (ASSYST)

GF00.20-P-0003-01A

Operating instructions, resetting
Model 210 as of 01.03.97 with engines M111,

OM 602, OM 604, OM 605 and

OM 606

As of 06/97 models 129, 140, 170, 202 except

engines 112, 113, 611

(valid for engines with oil level switch)
GF00.20-P-0003-01B

Copyright DaimlerChrysler AG 05.06.2006 CD-Ausgabe G/10/04 . This WIS print-out will not be recorde

d by Modification services.
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