2004 MERCEDES-BENZ G55AMG check engine

266 Practical hintsWhat to do if …Display symbol
Display message
Possible cause
Possible solution
#
UNDERVOLTAGE
SWITCH CONSUMERS OFF!
The battery has insufficient voltage.

Have the battery checked at a ser-
vice station.
2
BRAKE WEAR
VISIT WORKSHOP!
The brake pads have reached their
wear limit.

Have the brake pads replaced as
soon as possible.
3
BRAKE FLUID
VISIT WORKSHOP!
There is insufficient brake fluid in the
reservoir.

Risk of accident! Stop the vehicle
and notify an authorized
Mercedes-Benz Light Truck Center.
Do not add brake fluid! This will not
solve the problem.
Warning!
G
Driving with the last message displayed can
result in an accident. Have your brake sys-
tem checked immediately.
Do not add brake fluid before checking the
brake system. Overfilling the brake fluid res-
ervoir 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. !Brake pad thickness must be visually
checked by a qualified technician at the
intervals specified in the Service book-
let.

268 Practical hintsWhat to do if …Display symbol
Display message
Possible cause
Possible solution
B
COOLANT
CHECK LEVEL!
The coolant level is too low.

Add coolant (
page 232).

If you have to add coolant frequently,
have the cooling system checked by
an authorized Mercedes-Benz Light
Truck Center.
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 could be seriously burned.
!Do not ignore the low engine coolant
level warning. Extended driving with
the message and symbol displayed
may cause serious engine damage not
covered by the Mercedes-Benz Limited
Warranty.
Do not drive without sufficient amount
of coolant in the cooling system. The
engine will overheat causing serious
engine damage.
Observe the coolant temperature dis-
play (
page 112).

270 Practical hintsWhat to do if …Display symbol
Display message
Possible cause
Possible solution
Ï
COOLANT
STOP, ENGINE OFF!
The poly-V-belt could be broken.

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

Do not continue to drive. Otherwise
the engine will overheat due to an in-
operative water pump which may re-
s u l t i n d a m a g e t o t he e n g i n e . N ot i f y a n
authorized Mercedes-Benz Light Truck
Center.
If it is in order:

Do not continue to drive the vehicle
with this message displayed. Doing so
could result in serious engine damage
that is not covered by the
Mercedes-Benz Limited Warranty.
COOLANT
VISIT WORKSHOP!
The cooling fan for the coolant is malfunc-
tioning.

Observe the coolant temperature dis-
play (
page 112).

Have the fan replaced as soon as pos-
sible.

271 Practical hints
What to do if …
When the
ADD 1.0 QT. ENG. OIL
-
WHEN
NEXT REFUELLING!
(Canada:
1.0 LITER
)
message appears while the engine is run-
ning and at operating temperature, the en-
gine oil level has dropped to approximately
the minimum level.
When this occurs, the warning will first
come on intermittently and then stay on if
the oil level drops further.Visually check for oil leaks. If no obvious oil
leaks are noted, drive to the nearest ser-
vice station where the engine oil should be
topped to the required level with an ap-
proved oil.
Display symbol
Display message
Possible cause
Possible solution
Ñ
CRUISE CONTROL
DRIVE TO WORKSHOP!
Cruise control is malfunctioning.

Visit an authorized Mercedes-Benz
Light Truck Center.
J
DOOR OPEN!
You are attempting to drive with one or
more doors open.

Close the doors.
e
ENGINE AIR FILTER
VISIT WORKSHOP!
The engine filter is clogged and must be
replaced.

Visit an authorized Mercedes-Benz
Light Truck Center as soon as
possible.
:
USA only:ADD 1.0 Qt. ENGINE OIL
WHEN NEXT REFUELING!Canada only:ADD 1.0 LITER ENG. OIL
WHEN NEXT REFUELING!
The engine oil level is too low.

Add engine oil (
page 231) and check
the engine oil level (
page 229).
!The engine oil level warnings should
not be ignored. Extended driving with
the symbol displayed could result in se-
rious engine damage that is not cov-
ered by the Mercedes-Benz Limited
Warranty.

272 Practical hintsWhat to do if …Display symbol
Display message
Possible cause
Possible solution
:
ENGINE OIL LEVEL
REDUCE OIL LEVEL
!
You have added too much engine oil.
There is a risk of damaging the engine or
the catalytic converter.

Have oil siphoned or drained off. Ob-
serve all legal requirements with re-
spect to its disposal.
ENGINE OIL LEVEL
STOP, ENGINE OFF!
There is no oil in the engine. There is a
danger of engine damage.

Carefully bring the vehicle to a halt as
soon as possible.

Turn off the engine.

Add engine oil (
page 231) and check
the engine oil level (
page 229).
ENGINE OIL
VISIT WORKSHOP!
It may be that there is water in the engine
oil.

Have the oil checked.
ENGINE OIL LEVEL
VISIT WORKSHOP!
The engine oil has dropped to a critical
level.

Check the engine oil level
(page 229) and add oil as required
(page 231).

If you must add engine oil frequently,
have the engine checked for possible
leaks.
The measuring system is malfunctioning.

Have the measuring system checked
by an authorized Mercedes-Benz Light
Truck Center.

276 Practical hintsWhat to do if …Display symbol
Display message
Possible cause
Possible solution
.
LIGHT SENSOR
DRIVE TO WORKSHOP!
The lamp sensor is malfunctioning. The
headlamps switch on automatically.

In the control system, set lamp opera-
tion to manual (
page 129).

Switch on headlamps using the exteri-
or lamp switch (
page 104).

Visit an authorized Mercedes-Benz
Light Truck Center as soon as possi-
ble.
LICENSE PLATE LIGHT, L
CHECK LIGHT!

The left license plate lamp is malfunction-
ing.

Replace the bulb as soon as possible.
LICENSE PLATE LIGHT R
CHECK LIGHT!

The right license plate lamp is malfunc-
tioning.

Replace the bulb as soon as possible.
LIGHTS
TURN OFF LIGHTS!
The display appears if the driver’s door is
opened with the engine shut off and no
SmartKey in the starter switch.

Insert SmartKey in the starter switch.

Switch off the lights (
page 104).
LOW BEAM, L
CHECK LIGHT!
The left low beam lamp is malfunctioning.

Visit an authorized Mercedes-Benz
Light Truck Center as soon as possi-
ble.
LOW BEAM, R
CHECK LIGHT!
The right low beam lamp is malfunction-
ing.

Visit an authorized Mercedes-Benz
Light Truck Center as soon as possi-
ble.

313 Practical hints
Jump starting
Jump starting
If the battery is discharged, the engine can
be started with jumper cables and the bat-
tery of another vehicle. Observe the follow-
ing:

Jump starting should only be performed
when the engine and catalytic convert-
er are cold.


Do not start the engine if the battery is
frozen. Let the battery thaw out first.


Only use 12 volt battery to jump start
your vehicle. Jump starting with a more
powerful battery could damage the ve-
hicle’s electrical system, which will not
be covered by the Mercedes-Benz Lim-
ited Warranty.


Use only jumper cables with sufficient
cross-section and insulated terminal
clamps.


Always make sure the jumper cables
are not on or near pulleys, fans, or oth-
er parts that move when an engine is
started or running.
Warning!
G
Failure to follow these directions will cause
damage to the electronic components, and
can lead to a battery explosion and severe
injury or death.
Never lean over batteries while connecting
or jump starting, you might get injured.
Battery fluid contains sulfuric acid. Do not
allow this fluid to come in contact with eyes,
skin or clothing. In case it does, immediately
flush affected area with water, and seek
medical help if necessary.
A battery will also produce hydrogen gas,
which is flammable and very explosive. Keep
flames or sparks away from battery, avoid
improper connection of jumper cables,
smoking, etc.
Attempting to jump start a frozen battery
can result in it exploding, causing personal
injury.
Read all instructions before proceeding.
!Avoid repeated and lengthy starting at-
tempts.
Do not attempt to start the engine us-
ing a battery quick charge unit.
If engine does not run after several un-
successful starting attempts, have it
checked at the nearest authorized
Mercedes-Benz Light Truck Center.
Excessive unburned fuel generated by
repeated failed starting attempts may
damage the catalytic converter and
may present a fire risk.
Make sure the jumper cables do not
have loose or missing insulation.
Make sure the cable clamps do not
touch any other metal part while the
other end is still attached to a battery.!Do not tow-start the vehicle.

314 Practical hintsJump startingThe jump-start contacts are located in the
engine compartment.
Make sure the two vehicles do not
touch.

Turn off all electrical consumers.

Apply parking brake.

Shift gear selector lever to positionP.

Start engine of the vehicle with the
charged battery and run at idle speed.1Cover
2Positive (+) terminal
3Negative (-) terminal

Open cover1 of the positive terminal
of both vehicles.

Connect the positive terminals2 of
the batteries with the jumper cable.
Clamp cable to discharged battery first.

Connect negative terminals3 of the
batteries with the jumper cable. Clamp
cable to charged battery first.

Start the engine of the disabled vehi-
cle.Now you can again turn on the electrical
consumers. Do not turn on the lights under
any circumstances.

Remove the jumper cables first from
negative terminals3 of the batteries
and then from positive terminals2.
You can now turn on the lights.

Have the battery checked at the
nearest authorized Mercedes-Benz
Light Truck Center.
Warning!
G
Keep flames or sparks away from battery.
Do not smoke.
Observe all safety instructions and precau-
tions when handling automotive batteries
(page 311).