309 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 specified in the Factory 
Approved Service Products pamphlet.
Display symbol
Display message
Possible cause
Possible solution
: 
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 243) and check 
the engine oil level (
page 240).
!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.