engine MERCEDES-BENZ ML320 1997 Complete Repair Manual

236 OperationVehicle careEngine cleaning
Prior to cleaning the engine compartment
make sure to protect electrical compo-
nents and connectors from the intrusion of
water and cleaning agents.
Corrosion protection, such as MB Anticor-
rosion Wax, should be applied to the en-
gine compartment after every engine
cleaning. Before applying, all control link-
age bushings and joints should be lubricat-
ed. The poly-V-belt and all pulleys should
be protected from any wax.
Vehicle washing
Do not use hot water or wash your vehicle
in direct sunlight. Use only a mild car wash
detergent, such as Mercedes-Benz
approved Car Shampoo.Thoroughly spray the vehicle with a dif-
fused jet of water. Direct only a very weak
spray towards the ventilation intake. Use
plenty of water and rinse the sponge and
chamois frequently.
Rinse with clear water and thoroughly dry
with a chamois. Do not allow cleaning
agents to dry on the finish.
Due to the width of the vehicle, fold in out-
side mirrors prior to running the vehicle
through an automatic car wash to prevent
damage to the mirrors.
In the winter, thoroughly remove all traces
of road salt as soon as possible.
When washing the underbody, do not for-
get to clean the inner sides of the wheels.Ornamental moldings
For regular cleaning and care of very dirty
chrome-plated parts, use a chrome clean-
er.
Headlamps, tail lamps, side markers,
turn signal lenses
Use a mild car wash detergent, such as
Mercedes-Benz approved Car Shampoo,
with plenty of water.
To prevent scratches, never apply strong
force and use only a soft, non-scratchy
cloth when cleaning the lenses. Do not at-
tempt to wipe dirty lenses with a dry cloth
or sponge.

244 Practical hintsWhat to do if …Problem
Possible cause
Suggested solution
É
The red brake warning lamp
comes on while driving.
There is insufficient brake fluid in the reser-
voir.

Risk of accident! Carefully stop the
vehicle and notify an authorized
Mercedes-Benz Light Truck Center.
Do not add brake fluid! This will not
solve the problem.
É
The red brake warning lamp
comes on while driving and you
hear a warning sound.
You are driving with the parking brake set.

Release the parking brake
(page 47).
Warning!
G
Driving with the brake warning lamp illumi-
nated can result in an accident. Have your
brake system checked immediately if the
brake warning lamp stays on. Don’t add
brake fluid before checking the brake sys-
tem. Overfilling the brake fluid reservoir can
result in spilling brake fluid on hot engine
parts and the brake fluid catching fire. You
can be seriously burned.
!If you find that the brake fluid in the
brake fluid reservoir has fallen to the
minimum mark or below, have the
brake system checked for brake pad
thickness and leaks.

246 Practical hintsWhat to do if …Problem
Possible cause
Suggested solution
¿
The yellow BAS / ESP malfunc-
tion indicator lamp comes on
while driving.
The ESP is no longer synchronized following
a voltage supply interruption (e.g. battery dis-
connected or discharged).
Synchronize the ESP:
With vehicle stationary and the engine
running, turn the steering wheel
completely to the left and then to the
right.
If the BAS / ESP malfunction indicator
lamp does not go out:

Continue driving with added caution.

Visit an authorized Mercedes-Benz
Light Truck Center as soon as possi-
ble.
Failure to follow these instructions
increases the risk of an accident.
!When synchronizing the ESP, make
sure you can turn the steering wheel in
both directions as far as it will go with-
out the wheels hitting any objects, e.g.
a road curb.

248 Practical hintsWhat to do if …Problem
Possible cause
Suggested solution
?
The yellow “CHECK ENGINE”
malfunction indicator lamp
comes on while driving.
There is a malfunction of:

The fuel management system


The ignition system


The emission control system


Systems which affect emissions
Such malfunctions may result in excessive
emissions values and may switch the engine
to its limp-home (emergency operation)
mode.

Have the vehicle checked as soon as
possible by an authorized
Mercedes-Benz Light Truck Center.
An on-board diagnostic connector is
used by the service station to link the
vehicle to the shop diagnostics sys-
tem. It allows the accurate identifica-
tion of system malfunctions through
the readout of diagnostic trouble
codes. It is located in the front left
area of the footwell next to the park-
ing brake pedal.
The fuel cap is not closed tightly.
Check the fuel cap (
page 214).
Your fuel tank is empty.

After refuelling start the engine three
or four times in succession.
The limp-home mode is canceled. You do
not need to have your vehicle checked.

249 Practical hints
What to do if …
Problem
Possible cause
Suggested solution
/
The yellow coolant warning lamp
comes on when the engine is
running.
The coolant is to hot.
The coolant level is too low.

Stop as soon as possible and allow
the engine and coolant to cool down.

Check the coolant level and add
coolant if necessary (
page 222).
If the warning lamp comes on frequently,
there is a leak in the cooling system.

Have the cooling system checked by
an authorized Mercedes-Benz Light
Truck Center.
The coolant temperature gauge is above
248 °F (120 °C).
The coolant level is too low.

Stop as soon as possible and allow
the engine and coolant to cool down.

Add coolant to prevent engine from
overheating (
page 222).
If the coolant level is correct, the electrical
radiator fan may be broken.

If the coolant temperature is below
the red zone, drive on to the nearest
authorized Mercedes-Benz Light
Truck Center.
Avoid high engine loads (e.g. driving
uphill) and stop-and-go driving.

250 Practical hintsWhat to do if …Warning!
G
Driving when your engine is badly overheat-
ed can cause some fluids which may have
leaked into the engine compartment to
catch fire. You could be seriously burned.
Steam from an overheated engine can cause
serious burns and can occur just by opening
the engine hood. Stay away from the engine
if you see or hear steam coming from it.
Turn off the engine, get out of the vehicle
and do not stand near the vehicle until the
engine has cooled down.Warning!
G
Do not spill antifreeze on hot engine parts.
Antifreeze contains ethylene glycol which
may burn if it comes into contact with hot
engine parts. You can be seriously burned.
!Do not ignore the coolant warning
lamps. Extended driving with the sym-
bol displayed may cause serious engine
damage not covered by the
Mercedes-Benz Limited Warranty.
Do not drive without sufficient amount
of coolant. The engine will overheat,
causing major engine damage.

252 Practical hintsWhat to do if …Problem
Possible cause
Suggested solution
{
The yellow ETS malfunction indi-
cator lamp comes on while driv-
ing.
4-ETS has switched off to prevent overheat-
ing of the brakes. Also see 4-ETS / ESP warn-
ing lamp (
page 251).
As soon as the brakes have cooled off,
4-ETS switches on again.
The indicator lamp goes out.
4-ETS is malfunctioning and has switched off.

Have the 4-ETS checked at an autho-
rized Mercedes-Benz Light Truck Cen-
ter as soon as possible.
ê
The yellow LOW RANGE indicator
lamp flashes after one or more
switching conditions.
The gear selection conditions have not been
adhered to.

Repeat the gear selection process
(page 125).
ê
The yellow LOW RANGE indicator
lamp flashes after switching the
ignition on.
LOW RANGE mode is malfunctioning.
Have the LOW RANGE mode checked at
an authorized Mercedes-Benz Light Truck
Center.
The yellow fuel tank reserve
warning lamp comes on while
driving.
The fuel level has gone below the reserve
mark.

Refuel at the next gas station
(page 214).
The yellow fuel tank reserve
warning lamp flashes when leav-
ing the engine running.
The fuel cap is not closed tightly.

Check the fuel cap (
page 214).

253 Practical hints
What to do if …
Problem
Possible cause
Suggested solution
:
The yellow warning lamp flashes
after starting the engine or while
driving.
The engine oil level has sunk to the minimum
level. If the engine oil level continues to sink,
the warning lamp will light up.

Add approved oil at the next gas
station (
page 302).

If oil loss is visible on the engine, have
the malfunction corrected as soon as
possible at a Mercedes-Benz Light
Truck Center.
_
The red indicator lamp does not
go out after starting the engine.
The adjustable telescoping steering column
is not properly locked.

Lock the adjustable steering column
(page 39).
‡
The green front fog lamp indica-
tor lamp lights up when ignition
is turned on.
The front fog lamps are switched on.

Fog lamps (
page 111).
<
The red seat belt warning lamp
illuminates for a brief period
after starting the engine.
The warning lamp reminds you to fasten seat
belts.

Fasten your seat belt (
page 64).
W
The yellow low washer system
fluid level lamp comes on after
starting the engine or while driv-
ing.
There is approximately 1.3 US qt. (1.25 l) of
washer fluid remaining in the reservoir.

Add washer fluid (
page 224).
The washer fluid may have frozen.

Move the vehicle to a warmer environ-
ment so that the washer fluid will
thaw.

Correct the concentration level after
the washer fluid in the reservoir
thaws.

254 Practical hintsWhat to do if …Problem
Possible cause
Suggested solution
#
The red charge indicator lamp
comes on when the engine is
running.
The battery is no longer charging.
Possible causes:

alternator malfunctioning


broken poly-V-belt

Stop immediately and check the
poly-V-belt.
If it is broken

Do not continue to drive, before the
poly-V-belt is replaced.
Notify an authorized Mercedes-Benz
Light Truck Center.
2
The yellow brake indicator lamp
comes on during braking or after
starting the engine.
The brake pads are worn down.

Have the system checked at an autho-
rized Mercedes-Benz Light Truck
Center.
!Brake pad thickness must be visually
checked by a qualified technician at the
intervals specified in the Service book-
let.

275 Practical hints
Flat tire

On wheel to be changed, loosen but do
not yet remove the wheel bolts (ap-
proximately one full turn with wrench).
The jack take-up brackets are located di-
rectly behind the front wheel housings and
in front of the rear wheel housings.1Take-up bracket
2Jack

Place jack on firm ground.

Position jack2 under the take-up
bracket1 so that it is always vertical
(plumb-line) as seen from the side,
even if the vehicle is parked on an in-
cline.

Jack up the vehicle until the wheel is a
maximum of 1.2 in (3 cm) from the
ground. Never start engine while vehi-
cle is raised.
Warning!
G
The jack is designed exclusively for jacking
up the vehicle at the jack take-up brackets
built into both sides of the vehicle. To help
avoid personal injury, use the jack only to lift
the vehicle during a wheel change. Never
get beneath the vehicle while it is supported
by the jack. Keep hands and feet away from
the area under the lifted vehicle. Always
firmly set parking brake and block wheels
before raising vehicle with jack.
Do not disengage parking brake while the
vehicle is raised. Be certain that the jack is
always vertical (plumb line) when in use, es-
pecially on hills. Always try to use the jack
on level surface. Make sure that the jack
arm is fully seated in the jack take-up brack-
et. Always lower the vehicle onto sufficient
capacity jackstands before working under
the vehicle.
!Do not position the jack on the body of
the vehicle, as this may cause damage
to the vehicle.