Owners Manual

Display messages Possible causes/consequences and M Solutions
¯
DEF Chk
In addition, the yellow å DEF indicator lamp lights up and a
warning tone sounds.
The DEF supply has dropped below 1.5 US gal (5.5 l).
After the message appears for the first time and under normal
driving conditions, the remaining DEF supply will last for
approximately 1000 miles (1600 km).
After that, the 0.8 US gal (3.0 l) reserve mark is reached. A warning
tone sequence sounds and the engine can then only be started
another 16 times.
X
Add DEF supply (Y page 143).
After refilling, the system check takes approximately
20 seconds. The å DEF indicator lamp then goes out.
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StArtS RExx
In addition, the yellow ; engine diagnosis indicator lamp and
the yellow å DEF indicator lamp light up and a warning tone
sounds. A warning tone sequence sounds.
After the message appears for the first time, the engine can only
be started another 16 times.
The number of remaining engine starts xx (16 to 0) is shown in the
message every time the engine is started. Once the number 0 is
shown, the engine can no longer be started.
The DEF reducing agent is contaminated, diluted or is not
compliant with ISO 22241.
X
Have the DEF tank cleaned and refilled at a qualified specialist
workshop as soon as possible.
202
Troubleshooting
Practical advice