2008 MERCEDES-BENZ B-CLASS HATCHBACK engine

Troubleshooting
223Problem Possible cause/consequence Suggested solutions
The indicator lamp in the
F/
1 rear-window heating button
is flashing. The rear-window heat-
ing has switched itself off prema-
turely or cannot be switched on. The on-board voltage is too low,
because too many consumers are
switched on. X
Switch off consumers that are not required, e. g. reading lamp or
interior lighting.
Once the battery is sufficiently charged, the rear window heating
will switch back on automatically. Vehicles with automatic child
seat recognition on the front-
passenger seat:
The
5 PASSENGER AIRBAG
OFF warning lamp on the centre
console is lit. A special Mercedes-Benz child
seat with automatic child seat
recognition has been fitted to the
front-passenger seat. The front-
passenger airbag has therefore
been disabled as desired.
G
Risk of injury
There is no child seat fitted to the
front-passenger seat. The auto-
matic child seat recognition is
malfunctioning. X
Remove electronic equipment from the front-passenger seat, for
example
R
notebook
R mobile phone
R cards with transponders, e.g. ski passes or access passes
If the 5 PASSENGER AIRBAG OFF warning lamp is still lit:
X Visit a qualified specialist workshop. You have started the engine with
the key. The indicator lamp in the
ECO start/stop function* button
does not light up or goes out
again after a short time. You have deactivated the ECO
start/stop function*. X
Activate the ECO start/stop function* again. The ECO start/stop function*is
not available due to a fault. X
Visit a qualified specialist workshop. Practical advice
* optional
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Troubleshooting
224 Warning and indicator lamps in the instrument cluster
Problem Possible cause/consequence Suggested solutions
-
The yellow ABS warning
lamp comes on while the
engine is running. G
Risk of accident
ABS (Anti-lock Brake System) is
deactivated due to a fault. There-
fore, ESP ®
(Electronic Stability
Program), BAS (Brake Assist), the
steering assistant STEER CON-
TROL, the hill start assist and the
tyre pressure loss warning sys-
tem are also deactivated.
The brake system continues to
function normally, but without
electronic support. The wheels
could therefore lock if you brake
hard.
If the ABS control unit is faulty,
other systems may also not be
available: e.g. Parktronic sys-
tem*, the navigation system* or
the Autotronic*. X
Drive on carefully.
X Observe the additional messages in the multi-function display
(Y page 202).
X Visit a qualified specialist workshop. -
The yellow ABS warning
lamp comes on while the
engine is running. G
Risk of accident
The on-board voltage is too low.
ABS has been deactivated due to
undervoltage. X
Switch off consumers that are not required, e g. reading lamps or
interior lighting.
ABS will be available again as soon as the vehicle's electrical sys-
tem voltage increases. Practical advice
* optional
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Troubleshooting
225Problem Possible cause/consequence Suggested solutions
Therefore, ESP
®
, BAS, the steer-
ing assistant STEER CONTROL,
hill start assist and the tyre pres-
sure loss warning system are also
deactivated.
The brake system continues to
function normally, but without
electronic support. The wheels
could therefore lock if you brake
hard. v
The yellow ESP ®
warning
lamp is lit while the engine
is running. In addition, a
message appears in the
multi-function display. G
Risk of accident
ESP ®
is unavailable due to a mal-
function.
The following systems have also
been deactivated:
R BAS
R the steering assistant STEER
CONTROL
R hill start assist
R the tyre pressure loss warning
system
The braking system remains
available with full brake boosting
effect but without the above func-
tions. X
Observe the additional messages in the multi-function display
(Y page 202).
X Drive on carefully.
X Visit a qualified specialist workshop. Practical advice
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Troubleshooting
226 Problem Possible cause/consequence Suggested solutions
v
The yellow ESP ®
warning
lamp flashes while the
vehicle is in motion. G
Risk of accident
ESP ®
or traction control has
intervened because there is a risk
of skidding or at least one wheel
has started to spin. X
Only depress the accelerator pedal as far as necessary when pull-
ing away.
X Release the accelerator pedal while you are driving.
X Adapt your driving style to suit the road and weather conditions.
X Do not deactivate ESP ®
. 1
The red SRS warning lamp
is lit while the engine is
running. G
Risk of injury
There is a malfunction in the
restraint system. The airbags or
belt tensioners may either be trig-
gered unintentionally or, in the
event of an accident, not be trig-
gered at all. X
Visit a qualified specialist workshop immediately. 1
The red SRS warning lamp
is lit while the engine is
running. In addition, the
indicator lamp 5
PASSENGER AIRBAG OFF
flashes in the centre con-
sole and a warning tone
sounds. The connector on the removable
front-passenger seat* is
detached. X
Attach the connector to the coupling on the seat ( Ypage 155). H
The red brake system
warning lamp comes on
while you are driving. A
warning tone also sounds. You are driving with the parking
brake applied. X
Release the parking brake.
The warning lamp goes out and the warning tone ceases. Practical advice
* optional
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Troubleshooting
227Problem Possible cause/consequence Suggested solutions
H
The red brake system
warning lamp comes on
while the engine is run-
ning. G
Risk of accident
There is insufficient brake fluid in
the fluid reservoir. X
Pull over and stop the vehicle safely, paying attention to road and
traffic conditions. Do not continue driving under any circumstan-
ces.
X Consult a qualified specialist workshop immediately.
X Observe the additional messages in the multi-function display
(Y page 202).
Do not top up the brake fluid. This will not rectify the fault. ±
The yellow engine diagnos-
tics warning lamp lights up
while the engine is run-
ning. Vehicles with a diesel engine: the
fuel tank has been run dry. X
Start the engine three to four times after refuelling.
Emergency running mode is cancelled. The vehicle need not be
checked. ±
The yellow engine diagnos-
tics warning lamp lights up
while the engine is run-
ning. There may be a fault, for example
R
in the engine management
R in the ignition system
R in the exhaust system
R in the ignition system (for vehi-
cles with petrol engines)
The emission limit values may be
exceeded and the engine can run
in emergency mode. X
Have the vehicle checked as soon as possible at a qualified spe-
cialist workshop. Practical advice
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Troubleshooting
228 Problem Possible cause/consequence Suggested solutions
<
The red seat belt warning
lamp lights up for 6 sec-
onds after the engine
starts up 28
. The seat belt warning lamp
reminds the driver and front
passenger to fasten their seat
belts. X
Fasten your seat belt (Y page 72).<
After the engine starts, a
warning tone sounds for
up to 6 seconds 28
. G
Risk of injury
The driver's seat belt is not fas-
tened. X
Fasten your seat belt (Y page 72).
The warning tone ceases. <
The red seat belt warning
lamp lights up after the
engine starts, as soon as
the driver's door or the
front-passenger door is
closed. G
Risk of injury
The driver or front passenger has
not fastened their seat belt X
Fasten your seat belt (Y page 72).
The warning lamp goes out. G
Risk of injury
There are objects on the front-
passenger seat X
Remove the objects from the front-passenger seat and stow them
safely.
The warning lamp goes out. 28
Only for certain countries. Practical advice
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Troubleshooting
229Problem Possible cause/consequence Suggested solutions
<
The red warning lamp
flashes and an intermit-
tent audible warning
sounds. G
Risk of injury
The driver or front passenger has
not fastened their seat belt and
you are driving faster than
25 km/h or have briefly driven
faster than 25 km/h. X
Fasten your seat belt (Y page 72).
The warning lamp goes out and the intermittent audible warning
ceases. G
Risk of injury
There are objects on the front-
passenger seat and you are driv-
ing faster than 25 km/h or have
briefly driven faster than
25 km/h. X
Remove the objects from the front-passenger seat and stow them
safely.
The warning lamp goes out and the intermittent audible warning
ceases. The yellow engine diagnostics
warning lamp lights up while the
engine is running. The fuel level has fallen below the
reserve range. X
Refuel at the nearest filling station. Practical advice
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Troubleshooting
231Problem Possible cause/consequence Suggested solutions
You hear a warning tone.
Vehicles with AUTOTRONIC*:
You have:
R
switched off the engine
R opened the driver's door
R not moved the selector lever to
position P X
Move the selector lever to P.Accident
Problem Possible cause/consequence Suggested solutions
Fuel is leaking from the vehicle.
G
Risk of fire
The fuel line or the fuel tank has
been damaged. The leaking fuel
creates a risk of fire or explosion. X
Switch off the ignition immediately.
X Remove the ignition key.
Do not restart the engine under any circumstances. The leaking fuel
creates a risk of fire or explosion.
X Consult a qualified specialist workshop. You are unable to determine the
extent of the damage. X
Consult a qualified specialist workshop. You cannot detect any damage. X
Start the engine as normal. Practical advice
* optional
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