ECU MERCEDES-BENZ ML500 1997 Complete Repair Manual

Several situations may arise requiring some form of disposal action, including:
Scrapping a vehicle containing a deployed air bag module and/or ETR.
Scrapping a vehicle with a live air bag module and/or ETR.
Disposal of a live but electrically faulty air bag module and/or ETR.
Disposal of a deployed air bag module and/or ETR.
DEPLOYED AIR BAG OR ETR
Deployed air bag module and/or ETR unit can be thrown away. None of its components are reusable. Deployed
air bag module is NOT classified as hazardous material.
SCRAPPED VEHICLE
1. Before proceeding, follow service precautions. See SERVICE PRECAUTIONS . Move vehicle
outdoors to a remote area, away from workshop and other personnel. Disconnect and shield negative
battery cable. Open all vehicle windows and doors.
2. Ensure air bag module is secured to steering wheel, and passenger air bag is secured to dash. Ensure ETR
seat belt assemblies are secured to "B" pillars and all seat belt buckles are latched. Remove loose objects
from front seat. DO NOT allow anyone inside vehicle.
3. Disable air bag system. See DISABLING & ACTIVATING AIR BAG SYSTEM
. Connect Trigger
Device (126-589-00-90-00) and Adapter Cable (126 589 21 63 00) to SRS system connector (X29/9)
located at passenger footwell area. See Fig. 5
. Move away from vehicle as far as trigger device wiring
will allow.
4. To deploy driver air bag and ETR, turn rotary knob on trigger device to position No. 1. Push battery
check pushbutton and ignition pushbutton simultaneously. Trigger light should illuminate indicating
driver air bag and ETR deployed. If trigger light is illuminated and driver air bag and/or ETR did not
deploy, driver air bag module and/or ETR is faulty. See UNDEPLOYED AIR BAG/ETR
.
5. To deploy passenger air bag detonator No. 1, turn rotary knob on trigger device to position No. 2. Push
battery check pushbutton and ignition pushbutton simultaneously. Trigger light should illuminate
indicating passenger air bag detonator No. 1 deployed. If trigger light is illuminated and passenger air bag
detonator No. 1 did not deploy, passenger air bag module is faulty. See UNDEPLOYED AIR
BAG/ETR .
6. To deploy passenger air bag detonator No. 2, turn rotary knob on trigger device to position No. 3. Push
battery check pushbutton and ignition pushbutton simultaneously. Trigger light should illuminate
indicating passenger air bag detonator No. 2 deployed. If trigger light is illuminated and passenger air bag
detonator No. 2 did not deploy, passenger air bag module is faulty. See UNDEPLOYED AIR
BAG/ETR . WARNING:An undeployed air bag module and/or ETR seat belt CANNOT be disposed
of without first being deployed. If this is not possible through procedures
outlined below, contact vehicle manufacturer for further instructions.
Perform remote deployment outdoors. Keep personnel at least 20 feet
away.

1998 Mercedes-Benz ML320
AIR BAG RESTRAINT SYSTEM 1998 AIR BAG RESTRAINT SYSTEMS Mercedes-Benz
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passenger-side air bag module squib connector. Remove 4 passenger-side air bag module mounting nuts.
2. To install, reverse removal procedure. Ensure passenger-side air bag module squib connector audibly
clicks when connecting connector. Activate air bag system. Perform system operation check to ensure
system is functioning properly. See SYSTEM OPERATION CHECK
.
Removal & Installation (E Class)
1. Before proceeding, see SERVICE PRECAUTIONS . Disable air bag system. See DISABLING &
ACTIVATING AIR BAG SYSTEM . Remove ignition key. Remove 2 central mounting bolts for
passenger-side air bag module. Lift air bag module enough to unplug connector from rear of module.
Place module away from work area, with pad facing upward.
2. If necessary to replace passenger air bag installation frame, remove 4 frame mounting bolts. Remove
installation frame from vehicle.
3. To install air bag module or installation frame, reverse removal procedure. Activate air bag system.
Perform system operation check to ensure system is functioning properly. See SYSTEM OPERATION
CHECK .
Removal & Installation (S Class)
1. Before proceeding, see SERVICE PRECAUTIONS . Disable air bag system. See DISABLING &
ACTIVATING AIR BAG SYSTEM . Remove ignition key. Open glove box door. Remove 4 clips
securing glove box. Remove glove box compartment. When removing compartment, disconnect glove
box light. Remove glove box door lock striker.
2. Disconnect passenger-side air bag module squib connector. Remove 4 passenger-side air bag module
mounting nuts. Remove passenger-side air bag module through glove box opening. Place module away
from work area with pad facing up.
3. To install, reverse removal procedure. Ensure module squib connector audibly clicks when connecting
connector. Activate air bag system. Perform system operation check to ensure system is functioning
properly. See SYSTEM OPERATION CHECK
.
Removal & Installation (SL Class)
1. Before proceeding, see SERVICE PRECAUTIONS . Disable air bag system. See DISABLING &
ACTIVATING AIR BAG SYSTEM . Remove ignition key. Remove cover below instrument panel.
Remove one bolt in installation slot of center air outlet, and one bolt below right air outlet.
2. Remove air bag panel (3 Phillips screws and 2 hex bolts). Unplug connector at squib of passenger-side air
bag unit. Remove mounting bolts. Pull off and take air bag out of panel opening.
3. To install air bag module, reverse removal procedure. Activate air bag system. Perform system operation
check to ensure system is functioning properly. See SYSTEM OPERATION CHECK
.
Removal & Installation (CLK 320)
1. Before proceeding, see SERVICE PRECAUTIONS . Disable air bag system. See DISABLING &
ACTIVATING AIR BAG SYSTEM . Remove ignition key. Remove instrument panel. Disconnect
passenger-side air bag module connector. Remove 4 screws and passenger-side air bag module.
2. To install air ba
g module, reverse removal procedure. Activate air bag system. Perform system operation

1998 Mercedes-Benz ML320
AIR BAG RESTRAINT SYSTEM 1998 AIR BAG RESTRAINT SYSTEMS Mercedes-Benz
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During diagnosis, system values are continuously updated, so by moving components and connections
intermittent failures can be diagnosed. HHT will also display fault frequency and time span.
5. After retrieving fault codes using HHT, carefully observe testing instructions in this article. Some testing
is executed with HHT connected to DLC and some tests are executed with HHT removed from DLC.
Turn ignition off when removing or connecting HHT to DLC.
6. Contact Box (124 589 00 21) with Test Cable (124 589 35 63) is necessary to complete some test steps.
Resistance Substitution Unit (124 589 09 63) is necessary to substitute resistance values for testing
purposes.
Fig. 6: Hand Held Tester Graphic Information

Courtesy of MERCEDES-BENZ OF NORTH AMERICA

1998 Mercedes-Benz ML320
AIR BAG RESTRAINT SYSTEM 1998 AIR BAG RESTRAINT SYSTEMS Mercedes-Benz
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25 Central locking system
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Reserve key
The reserve key fits all locks on the vehicle.
For notes on the mechanical keys refer to page 29.
Note:
We recommend that you carry the reserve key with you
and keep it in a safe place (e.g. your wallet) so that it is
always handy. Never leave the reserve key in the
vehicle.Obtaining replacement keys
Your vehicle is equipped with a theft deterrent locking
system requiring a special key manufacturing process.
For security reasons, replacement keys can only be
obtained from your authorized Mercedes-Benz Light
Truck Center.
Start lock-out
Important!
Removing the key from the steering lock activates the
start lock-out. The engine cannot be started.
Turning the key in the steering lock to position 2
deactivates the start lock-out.
Note:
In case the engine cannot be started and the
messagesÁ and î are shown in the odometer
display field, the system is not operational. Contact an
authorized Mercedes-Benz Light Truck Center or call
1-800-FOR-MERCedes (in the USA), or 1-800-387-0100
(in Canada).

38 Seats
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Important!
Prior to operating the vehicle, the driver should adjust
the seat height for proper vision as well as fore / aft
placement and backrest angle to insure adequate
control, reach, operation, and comfort. The head
restraint should also be adjusted for proper height. See
also airbag section on page 56 for proper seat
positioning.
In addition, also adjust the steering wheel to ensure
adequate control, reach, operation, and comfort.
Both the inside and outside rear view mirrors should be
adjusted for adequate rearward vision.
Fasten seat belts. Infants and small children should be
seated in a properly secured restraint system that
complies with U.S. Federal Motor Vehicle Safety
Standard 213 and Canadian Motor Vehicle Safety
Standard 213.
All seat, head restraint, steering wheel, and rear view
mirror adjustments as well as fastening of seat belts
should be done before the vehicle is put into motion.
Wa r n i n g !
Children 12 years old and under must never ride in
the front seat, except in a Mercedes-Benz
authorized BabySmart
TM compatible child seat,
which operates with the BabySmart
TM system
installed in the vehicle to deactivate the passenger
side front airbag when it is properly installed.
Otherwise they will be struck by the airbag when it
inflates in a crash. If this happens, serious or fatal
injury can result.
According to accident statistics, children are safer
when properly restrained in the rear seating
positions than in the front seating positions.
Infants and small children must ride in the back
seats and be seated in an appropriate infant or
child restraint system, which is properly secured
with the vehicle’s seat belt, fully in accordance
with the child seat manufacturer’s instructions.A child’s risk of serious or fatal injuries is
significantly increased if the child restraints are
not properly secured in the vehicle and the child is
not properly secured in the child restraint.

46 Restraint systems
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Seat belts and integrated restraint system
Your vehicle is equipped with seat belts for all seats,
emergency tensioning retractors for front and second
row outboard seat belts, dual front airbags and door
mounted side impact airbags. Their protective functions
are designed to complement one another.
Seat belts
Important!
Laws in most states and all Canadian provinces require
seat belt use.
All states and provinces require use of child restraints
that comply with U.S. Federal Motor Vehicle Safety
Standard 213 and Canadian Motor Vehicle Safety
Standard 213.
All child restraint systems are designed to be secured in
vehicle seats by lap belts or the lap belt portion of a lap-
shoulder belt.
For your safety and that of your passengers we strongly
recommend their use.
Wa r n i n g !
Children 12 years old and under must never ride in
the front seat, except in a Mercedes-Benz
authorized BabySmart
TM compatible child seat,
which operates with the BabySmart
TM system
installed in the vehicle to deactivate the passenger
side front airbag when it is properly installed.
Otherwise they will be struck by the airbag when it
inflates in a crash. If this happens, serious or fatal
injury will result.
According to accident statistics, children are safer
when properly restrained in the rear seating
positions than in the front seating positions.
Infants and small children must ride in back seats
and be seated in an appropriate infant or child
restraint system, which is properly secured with
the vehicle’s seat belt, fully in accordance with the
child seat manufacturer’s instructions.A child’s risk of serious or fatal injuries is
significantly increased if the child restraints are
not properly secured in the vehicle and the child is
not properly secured in the child restraint.

52 Restraint systems
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Wa r n i n g !
USE CHILD RESTRAINTS PROPERLY.Children 12 years old and under must never ride in
the front seat, except in a Mercedes-Benz
authorized BabySmart
TM compatible child seat,
which operates with the BabySmart
TM system
installed in the vehicle to deactivate the passenger
front airbag when it is properly installed.
Otherwise they will be struck by the airbag when it
inflates in a crash. If this happens, serious or fatal
injury will result.
According to accident statistics, children are safer
when properly restrained in the rear seating
positions than in the front seating positions.
Infants and small children must ride in back seats
and be seated in an appropriate infant or child
restraint system, which is properly secured with
the vehicle’s seat belt, fully in accordance with the
child seat manufacturer’s instructions.
A child’s risk of serious or fatal injuries is
significantly increased if the child restraints are
not properly secured in the vehicle and the child is
not properly secured in the child restraint.Children too big for child restraint systems must
ride in back seats using regular seat belts. Position
shoulder belt across chest and shoulder, not face or
neck. A booster seat may be necessary to achieve
proper belt positioning.

65 Restraint systems
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Infant and child restraint systems
We recommend t ha t all infa nts and children be properly
restrained at all times while the vehicle is in motion. All
lap-shoulder belts except the driver’s seat belt have
special seat belt retractors for secure fastening of child
restraints.
To fasten a child restraint follow child restraint
instructions for routing. Then pull shoulder belt out
completely and let it retract. During the seat belt
retraction a ratcheting sound can be heard to indicate
that the special seat belt retractor is activated. The belt
is now locked. Push down on child restraint to take up
any slack.
To deactivate, release seat belt buckle and let seat belt
retract completely. The seat belt can again be used in
the usual manner.
Note:
For child seats with mounting fittings for tether
anchorages refer to page 67 (installation of infant and
child restra int systems).Important!
The use of infant or child restraints is required by law in
all 50 states and all Canadian provinces.
Infants and small children should be seated in an
appropriate infant or child restraint system properly
secured by a lap-shoulder belt, and that complies with
U.S. Federal Motor Vehicle Safety Standard 213 and
Canadian Motor Vehicle Safety Standard 213.
A statement by the child restraint manufacturer of
compliance with this standard can be found on the
instruction label on the restraint and in the instruction
manual provided with the restraint.
When using any infant or child restraint system, be sure
to carefully read and follow all manufacturer’s
instructions for installation and use.
Please read and observe warning labels affixed to inside
of vehicle and to infant or child restraints.
Wa r n i n g !
Never release the seat belt buckle while vehicle is
in motion, since the special seat belt retractor will
be deactivated.

66 Restraint systems
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index
Wa r n i n g !
Children 12 years old and under must never ride in
the front seat, except in a Mercedes-Benz
authorized BabySmart
TM compatible child seat,
which operates with the BabySmart
TM System
installed in the vehicle to deactivate the passenger
front airbag when it is properly installed.
Otherwise they will be struck by the airbag when it
inflates in a crash. If this happens, serious or fatal
injury can result.
According to accident statistics, children are safer
when properly restrained in the rear seating
positions than in the front seating positions.
Infants and small children must ride in back seats
and be seated in an infant or child restraint system,
which is properly secured with the vehicle’s seat
belt, fully in accordance with the child seat
manufacturer’s instructions.
Infants and small children should never share a
seat belt with another occupant. During an
accident, they could be crushed between the
occupant and seat belt.Children too big for child restraint systems must
ride in back seats using regular seat belts. Position
shoulder belt across chest and shoulder, not face or
neck. A booster seat may be necessary to achieve
proper belt positioning for children from 41 lbs. to
the point where a lap / shoulder belt fits properly
without one.When the child restraint is not in use, remove it
from the vehicle or secure it with the seat belt to
prevent the child restraint from becoming a
projectile in the event of an accident.

67 Restraint systems
Te ch n ica l
data Instruments
and controlsOperationDrivingInstrument
cluster displayPractical hints Car care Index Installation of infant and child restraint systems
To secure a tether strap to the anchorage, securely
fasten the hook (1), which is part of the tether strap, to
the anchorage ring (2). For safety, please make sure that
the hook has attached to the ring beyond the safety
catch, as illustrated.Vehicle without third row seats
3Tether anchorages for second row seats
4Tether anchorages for third row seats (optional)
This vehicle is provided with three tether
anchorages (3) for a top tether strap behind the
second row seats.
Note:
Do not use the tether anchorages (4) for a top tether
strap on a second row seat.