Page 578 of 723
575 Practical hints
What to do if …?
ProblemPossible cause/consequenceSuggested solution
=The red SRS indicator lamp
comes on while the engine is
running.There is a malfunction in the supplemental
restraint systems. The air bags or emergen-
cy tensioning devices (ETDs) could deploy
unexpectedly or fail to deploy in an
accident.Drive with added caution to the nearest
authorized Mercedes-Benz Center.
Warning!G
In the event that a malfunction of the SRS is
indicated as outlined above, the SRS may
not be operational. For your safety, we
strongly recommend that you contact an au-
thorized Mercedes-Benz Center immediate-
ly to have the system checked; otherwise
the SRS may not be deployed when needed
in an accident, which could result in serious
or fatal injury, or it might deploy unexpect-
edly and unnecessarily which could result in
an accident and/or injury to you or to
others.
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Page 594 of 723

591 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Shift to P or N
to start engineYou have attempted to start the engine
while the automatic transmission was set to
position R or D.Shift the automatic transmission to P or N (page 389).
Tire pressure monitor
inoperativeThe Advanced TPMS or a wheel sensor is
malfunctioning.Have the Advanced TPMS checked by an authorized
Mercedes-Benz Center.
Tire pressure monitor
inoperative
No wheel sensorsThe Advanced TPMS is deactivated because
wheels without proper sensors were in-
stalled.Have the wheel sensors installed by an authorized
Mercedes-Benz Center.
As soon as all wheels with sensors have been mounted, the
Advanced TPMS is switched back on after driving for several
minutes.
Tire pressure monitor
currently unavailableThe Advanced TPMS is unable to monitor
the tire inflation pressure due to:
a nearby radio interference source
the on-board voltage is too low
excessive wheel sensor temperatures
As soon as the causes for the malfunction are no longer present,
the Advanced TPMS automatically becomes active again after a
few minutes driving.
Warning!G
Do not drive with a flat tire. A flat tire affects
the ability to steer or brake the vehicle. You
may lose control of the vehicle.
Continued driving with a flat tire will cause
excessive heat build-up and possibly a fire.
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Page 599 of 723

596 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Check brake
fluid levelThere is insufficient brake fluid in the reser-
voir.Risk of accident!
Carefully stop the vehicle in a safe location or
as soon as it is safe to do so.
Engage the electronic parking brake
(
page 637).
Contact an authorized Mercedes-Benz Cen-
ter.
Do not add brake fluid! This will not solve the
problem.
(USA only)
(Canada only)
Warning!G
Driving with the message “Check brake fluid
level ” displayed can result in an accident.
Have your brake system checked immedi-
ately. Do not add brake fluid before check-
ing the brake system. Overfilling the brake
fluid reservoir can result in spilling brake flu-
id 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.
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Page 609 of 723
606 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Inoperative
See Oper. ManualCL 600 only:
ESP
® a s w e l l a s P R E - S A F E® are switched off
due to a malfunction. In addition, the v
and ; (USA only) or 3(Canada only)
warning lamps come on in the instrument
cluster.
Brake force assistance is impaired and is
sustained through an electric substitute
function as long as the engine is running.
The brake system continues to function
normally. You will feel a pulsating effect at
the brake pedal while braking.
BAS Plus* and PRE-SAFE
® Brake* are also
not available.
Continue driving with added caution.
Have the system checked at an authorized
Mercedes-Benz Center as soon as possible.
Failure to follow these instructions increases the
risk of an accident.
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Page 612 of 723
609 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Coolant,
please refill
See Oper. ManualThe coolant level is too low.Add coolant (page 518).
If you have to add coolant frequently, have
the cooling system checked by an authorized
Mercedes-Benz 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 Lim-
ited Warranty.
Do not drive without a sufficient amount of cool-
ant in the cooling system. The engine will over-
heat, causing major engine damage.
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Page 614 of 723
611 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Coolant level
Stop vehicle!
Switch engine offThe poly-V-belt could be broken.Stop the vehicle in a safe location or as soon
as it is safe to do so and immediately turn off
the engine.
Check the poly-V-belt.
If it is broken:
Do not continue to drive. Otherwise the en-
gine will overheat due to an inoperative water
pump which may result in damage to the en-
gine.
Notify an authorized Mercedes-Benz Center.
If it is intact:
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.
Observe the coolant temperature gauge in
the instrument cluster (
page 30).
(Continued on next page)
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Page 626 of 723
623 Practical hints
What to do if …?
Display Possible cause/consequencePossible solution
Night View Assist
Lights ON or AUTO,
not in R gearYou have tried to switch on Night View
Assist* but the light switch is not set
to*or B.
In addition, the automatic transmission is in
positionR.Turn the exterior lamp switch
to*orB (
page 363).
Shift the automatic transmission to P, N or D
(
page 389).
Night View Assist
only when
it is darkYou have tried to switch on Night View
Assist* by daylight.You can only switch on Night View Assist* when
it is dark.
Engine oil level
Stop vehicle!
Switch engine offCL 600 only
There is no oil in the engine. There is a dan-
ger of engine damage.Carefully bring the vehicle to a halt as soon
as it is safe to do so in a safe location.
Turn off the engine.
Add engine oil (page 516) and check the
engine oil level (
page 513).
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Page 627 of 723

624 Practical hints
What to do if …?
When the message “Check engine oil level
at next refueling” (CL 550) or “Add 1.0 qts.
(Canada:1.0 l) engine oil at next refueling”
(CL 600) 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.
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 Center.
Display Possible cause/consequencePossible solution
USA only:
Add 1.0 qts. engine oil
at next refueling
(USA only)
Add 1.0 l engine oil
at next refueling
(Canada only)CL 600 only:
The engine oil level is too low.Check the engine oil level (page 513) and
add engine oil as required (
page 516).
If you must add engine oil frequently, have
the engine checked for possible leaks.
Check engine oil level
at next refuelingCL 550 only:
The engine oil level has dropped to approx-
imately the minimum level.Check the engine oil level (page 513) and
add engine oil as required (
page 516).
If you must add engine oil frequently, have
the engine checked for possible leaks.
!The engine oil level warnings should not be
ignored. Extended driving with the symbol dis-
played could result in serious engine damage
that is not covered by the Mercedes-Benz Limit-
ed Warranty.
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