2000 MERCEDES-BENZ M320 check engine light

219 Malfunction and indicator lamps
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index Brake warning lamp
When the brake warning lamp appears
while the engine is running, this means:
•there is insufficient brake fluid in the reservoir
(engine running and parking brake released), or
•the parking brake is set (engine running)
•the electronic brake proportioning (EBP) system is
malfunctioning.
Note:
If you find that the minimum mark on the brake fluid
reservoir is reached, have the brake system checked for
brake pad thickness and leaks.Supplemental restraint system (SRS) indicator lamp
The operational readiness of the airbag
system is verified by the indicator lamp
“SRS” in the instrument cluster when
turning the key in steering lock to position 1 or 2. If no
fault is detected, the lamp will go out after
approximately 5 seconds; after the lamp goes out, the
system continues to monitor the components and
circuitry of the airbag system and will indicate a
malfunction by coming on again.
See page 56 for notes on airbags, page 55 for belt
tensioners, and page 65 for infant and child seat
restraints.
Wa r n i n g !
Driving with the brake warning lamp illuminated
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 system. 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.BRAKE
Wa r n i n g !
In the event a malfunction of the “SRS” is indicated
as outlined above, the “SRS” may not be
operational. For your safety, we strongly
recommend that you visit an authorized
Mercedes-Benz Light Truck Center immediately to
have the system checked; otherwise the “SRS” may
not be activated when needed in an accident, which
could result in serious or fatal injury, or it might
deploy unexpectedly and unnecessarily which
could also result in injury.SRS

222 Malfunction and indicator lamps
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
ABS malfunction indicator lamp
The ABS malfunction indicator lamp in the
instrument cluster comes on with the key in
steering lock position 2 and should go out
with the engine running.
When the ABS malfunction indicator lamp in the
instrument cluster comes on while the engine is
running, it indicates that the ABS has detected a
malfunction and has switched off. In this case, the brake
system functions in the usual manner, but without
antilock assistance.
With the ABS malfunctioning, the BAS, ESP and 4-ETS+
are also switched off. Both malfunction indicator lamps
come on with the engine running.
If the charging voltage falls below 10 volts, the
malfunction indicator lamp comes on and the ABS is
switched off. When the voltage is above this value again,
the malfunction indicator lamp should go out and the
ABS is operational.
Have the system checked at your authorized
Mercedes-Benz Light Truck Center as soon as possible.
See page 201 for notes on antilock brake system (ABS).Adjustable steering wheel – indicator lamp
The indicator lamp in the instrument cluster
comes on with the key in steering lock
position 2 and should go out with the engine
running.
If the indicator lamp does not go out after starting the
engine, the adjustable steering column is not properly
locked.
For locking the adjustable telescoping steering column,
see page 70.
AIRBAG OFF indicator lamp
The indicator lamp will light up for
approximately 6 seconds, extinguish, then
blink once, when you turn the key in
steering lock to position 1 or 2.
The 7 indicator lamp stays lit as long as a
BabySmart
TM compatible child seat is properly installed
on the front passenger seat. It indicates that the front
passenger airbag is switched off.
See page 53 for BabySmart
TM airbag and its deactivation
system.
BabySmart
TM is a trademark of Siemens Automotive Corp.
ABS

224 Malfunction and indicator lamps
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index
Low engine oil level warning lamp
With the key in steering lock position 2, the
oil level warning lamp comes on and should
go out when the engine is running.
If the warning lamp does not go out after starting the
engine, or comes on with the engine running and at
operating temperature, the engine oil level has dropped
to approximately the minimum mark on the dipstick.
When this occurs, the warning lamp 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 “full” mark on the dipstick with an approved oil.
The low engine oil level warning light should not be
ignored. Extended driving with the light illuminated
could result in serious engine damage that is not
covered by the Mercedes-Benz Limited Warranty.
In addition to the warning lamp, the engine oil level
should be periodically checked with the dipstick or via
the oil level indicator in the odometer display field, for
example during a fuel stop, or before a long trip (see
engine oil level indicator on page 89 and checking
engine oil on page 233).Low engine coolant level warning
When the coolant level warning lamp comes
on while driving, then the coolant level has
dropped below the required level, or the
coolant temperature is in the red zone. If no leaks are
noticeable and the engine temperature does not
increase, continue to drive to the nearest service station
and have coolant added to the coolant system, see
page 234. If the engine temperature reaches the red
zone, move vehicle to an area which is in a safe distance
from the roadway and turn off the engine. Also see
coolant temperature gauge on page 81.
The low engine coolant level warning should not be
ignored. Extended driving with the symbol displayed
may cause serious engine damage not covered by the
Mercedes-Benz Limited Warranty.
In cases of major or frequent minor coolant loss, have
the cooling system checked at your authorized
Mercedes-Benz Light Truck Center as soon as possible.
Notes:
Do not drive without coolant in the cooling system. The
engine will overheat causing major engine damage.
Monitor the coolant temperature gauge while driving.

225 Malfunction and indicator lamps
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index Brake pad wear indicator lamp
With the key in steering lock position 2, the
indicator lamp comes on and goes out when
the engine is running.
If the indicator lamp lights up during braking, this
indicates that the brake pads are worn down.
Have the brake system checked at your authorized
Mercedes-Benz Light Truck Center as soon as possible.FSS indicator
FSS indicator (Service A), see page 87.
FSS indicator (Service B), see page 87.
The symbols appear in the main odometer display field
prior to the next suggested service. Depending on
operating conditions throughout the year, the next
service is calculated and displayed in days or distance
remaining. See page 87 for notes on the flexible service
system (FSS).

234 Engine compartment
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index
Automatic transmission fluid level
The transmission has a permanent fill of automatic
transmission fluid.
Regular automatic transmission fluid level checks and
changes are not required. For this reason the dipstick is
omitted.
If you notice fluid leaks or gear shifting malfunctions,
have your authorized Mercedes-Benz Light Truck Center
check the transmission fluid level.
Engine oil consumption
Engine oil consumption checks should only be made
after the break-in period. During the break-in period,
higher oil consumption may be noticed and is normal.
Frequent driving at high engine speeds results in
increased consumption.Coolant level
To check the coolant level, the vehicle must be parked
on level ground and the engine stopped.
Check coolant level only when coolant is cold.
The coolant level should reach the COLD LEVEL mark in
the reservoir.P20.30-0241-20

254 Jump starting
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hintsCar care Index
Proceed as follows:
1. Position the vehicle with the charged battery so that
the jumper cables will reach, but never let the
vehicles touch. Make sure the jumper cables do not
have loose or missing insulation.
2. On both vehicles:
•Turn off engine and all lights and accessories,
except hazard warning flashers or work lights.
•Apply parking brake and shift selector lever to
position “P”.
Important!
3. Clamp one end of the first jumper cable to the
positive (+) under hood terminal of the discharged
battery and the other end to the positive (+) terminal
of the charged battery. Make sure the cable clamps
do not touch any other metal parts.
4. Clamp one end of the second jumper cable to the
grounded negative (–) terminal of the charged
battery and the final connection to the negative (–)
terminal of the discharged battery.Important!
5. Start engine of the vehicle with the charged battery
and run at high idle. Make sure the cables are not
on or near pulleys, fans, or other parts that move
when the engine is started. Allow the discharged
battery to charge for a few minutes. Start engine of
the disabled vehicle in the usual manner.
6. After the engine has started, remove jumper cables
by exactly reversing the above installation
sequence, starting with the last connection made
first. When removing each clamp, make sure that it
does not touch any other metal while the other end
is still attached.
Notes:
If engine does not run after several unsuccessful
starting attempts, have it checked at the nearest
authorized Mercedes-Benz Light Truck Center.
Excessive unburned fuel may damage the catalytic
converter.

297 Fuels, coolants, lubricants etc.
Te ch n ica l
data Instruments
and controlsOperation DrivingInstrument
cluster displayPractical hints Car care Index the engine temperature will increase due to the lower
heat transfer capability of the solution. Therefore, do not
use more than this amount of anticorrosion / antifreeze.
If the coolant level is low, water and MB anticorrosion/
antifreeze should be used to bring it up to the proper
level (have cooling system checked for signs of leakage).
The water in the cooling system must meet minimum
requirements, which are usually satisfied by normal
drinking water. If your are not sure about the water
quality, consult your authorized Mercedes-Benz Light
Truck Center.
Anticorrosion/antifreeze
Your vehicle contains a number of aluminum parts. The
use of aluminum components in motor vehicle engines
necessitates that anticorrosion / antifreeze coolant used
in such engines be specifically formulated to protect the
aluminum parts. (Failure to use such anticorrosion/
antifreeze coolant will result in a significantly
shortened service life.)
Therefore the following product is strongly
recommended for use in your vehicle: Mercedes-Benz
Anticorrosion / antifreeze agent.Before the start of the winter season (or once a year in
the hot southern regions), you should have the
anticorrosion / antifreeze concentration checked. The
coolant is also regularly checked each time you bring
your vehicle to your authorized Mercedes-Benz Light
Truck Center for service.
Anticorrosion / antifreeze quantity
Approx. freeze protection
– 35°F
(– 37°C)– 49°F
(– 45°C)
6.4 US qt
(6.0 l)7. 0 U S q t
(6.6 l)