2007 MERCEDES-BENZ G55AMG check engine

344 Practical hints
What to do if …
Symbol messages
Display symbolDisplay messagePossible cause/consequencePossible solution
#The battery is no longer charging.
Possible causes:

alternator malfunctioning

broken poly-V-belt
Stop the vehicle in a safe location or as soon
as it is safe to do so.
Apply the parking brake (page 62).
Turn off the engine.
Check the poly-V-belt.
If it is broken:
Do not continue to drive.
Otherwise, the engine will overheat due to an
inoperative water pump which may result in
damage to the engine.
Contact an authorized Mercedes-Benz Light
Truck Center.
If it is in order:
Contact an authorized Mercedes-Benz Light
Truck Center immediately.

346 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
3Check brake
fluid levelThere is insufficient brake fluid in the
reservoir.Risk of accident!
Carefully stop the vehicle in a safe location or
as soon as it is safe to do so.
Apply the parking brake (page 62).
Do not drive any further.
Contact an authorized Mercedes-Benz Light
Truck Center.
Do not add brake fluid! This will not solve the
problem.
Warning!G
Driving with the message Check brake
fluid level
displayed can result in an
accident. Have your brake system 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.

347 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
;(USA only)
! (Canada only)
Release
parking
brakeYou are driving with the parking brake
set.Release the parking brake
(
page 55).
2Brake
wearThe brake pads have reached their wear
limit.Have the brake pads replaced as
soon as possible.
BTop up
coolant
See
Operator’s
ManualThe coolant level is too low.Add coolant (page 274).
If you have to add coolant frequently,
have the cooling system checked at
an authorized Mercedes-Benz Light
Truck Center.
!Brake pad thickness must be visually
checked by a qualified technician at the intervals
specified in the Maintenance Booklet.
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 this 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 major engine damage.

348 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
•Coolant
Stop, turn
engine offThe coolant is too hot.
Among other possible causes, the
poly-V-belt could be broken.Stop the vehicle in a safe location or as soon
as it is safe to do so.
Apply the parking brake (page 62).
Turn off the engine.
Check the poly-V-belt.
If it is broken:
Do not continue to drive.
Otherwise, the engine will overheat due to an
inoperative water pump which may result in
damage to the engine.
Contact an authorized Mercedes-Benz Light
Truck Center.
If it is in order:
Wait for the message to disappear before
restarting the engine.
Doing otherwise could result in serious engine
damage that is not covered by the
Mercedes-Benz Limited Warranty.
(Continued on next page)

350 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
•The cooling fan for the coolant is
malfunctioning.Observe the coolant temperature
gauge in the multifunction display
(
page 26).
If the coolant temperature is
below 120°C, you may continue
driving to the nearest specialist
workshop.
Avoid placing heavy loads on the
engine (e.g. by driving uphill) as well as
stop-and-go traffic.
Have the fan replaced as soon as
possible.
ÑCr. control
and SPEED-
TRONIC
inoperativeThe cruise control is malfunctioning.Have the cruise control checked at an
authorized Mercedes-Benz Light Truck
Center.
JYou are attempting to drive with one or
more doors open.Close the doors.

351 Practical hints
What to do if …
When the message At next gas station
add 1.0 qt engine oil

(Canada:
1.0 liter) appears while the
engine is running and at operating
temperature, the engine 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 oil leaks
are noted, continue to drive to the nearest
service station where the engine oil should
be topped to the required level with an
approved engine oil. For information on
approved engine oils, refer to the Factory
Approved Service Products pamphlet
(USA only) or contact an authorized
Mercedes-Benz Light Truck Center.
Display symbolDisplay messagePossible cause/consequencePossible solution
:USA only:
At next
gas station
add
1.0 qt
engine oil
Canada only:
At next
gas station
add
1.0 liter
engine oil
The engine oil level is too low.Add engine oil (page 273) and check
the engine oil level (
page 270).

352 Practical hints
What to do if …
Display symbolDisplay messagePossible cause/consequencePossible solution
:Engine oil
level
Stop, turn
engine offThere is no oil in the engine. There is
a danger of engine damage.Stop the vehicle in a safe location or as soon as
it is safe to do so.
Turn off the engine.
Add engine oil (page 273) and check the
engine oil level (
page 270).
Engine oil
level
Visit
workshopThe engine oil has dropped to a
critical level.Check the engine oil level (page 270) and add
engine oil as required (
page 273).
If you must add engine oil frequently, have the
engine checked for possible leaks.
You have added too much engine oil.
There is a risk of damaging the engine
and/or the catalytic converter.Have excess oil siphoned or drained off.
Observe all legal requirements with respect to
its disposal.
It may be that there is water in the
engine oil.Have the engine oil checked at an authorized
Mercedes-Benz Light Truck Center.
The measuring system is malfunction-
ing.Have the measuring system checked at an
authorized Mercedes-Benz Light Truck Center.
!The engine oil level warnings should not be
ignored. Extended driving with the symbol
displayed could result in serious engine damage
that is not covered by the Mercedes-Benz
Limited Warranty.

396 Practical hints
Battery
The battery is located in front of the rear
seat bench and below the cup holder.
Jump starting terminals are located on the
driver’s side of the engine compartment
(
page 400).
The battery should always be sufficiently
charged in order to achieve its rated
service life. Refer to Maintenance Booklet
for battery maintenance intervals.
If you use your vehicle mostly for
short-distance trips, you will need to have
the battery charge checked more
frequently.
When replacing the battery, always use
batteries approved by Mercedes-Benz.
If you do not intend to operate your vehicle
for an extended period of time, consult an
authorized Mercedes-Benz Light Truck
Center about steps you need to observe.Batteries contain materials that can harm
the environment if disposed of improperly.
Large 12-volt storage batteries contain
lead. Recycling of batteries is the preferred
method of disposal. Many states require
sellers of batteries to accept old batteries
for recycling.
iMercedes-Benz recommends to have the
battery replaced at an authorized
Mercedes-Benz Light Truck Center.
Warning!G
Observe all safety instructions and precau-
tions when handling automotive batteries.
Risk of explosion.
Fire, open flames and smoking
are prohibited when handling
batteries. Avoid creating sparks.
Battery acid is caustic. Do not
allow it to come into contact
with skin, eyes or clothing.
Wear suitable protective cloth-
ing, especially gloves, apron and
faceguard.
Wear eye protection.
Rinse any acid spills imme-
diately with clear water. Contact
a physician if necessary.
Keep children away.
Follow the instructions in this
Operator’s Manual.