Mercedes-Benz E-Class Operator's Manual page 61

Problem
You have lost a SmartKey.
Possible causes/consequences and
The SmartKey is faulty.
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Check the battery using the battery check lamp and replace if necessary .
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Use the emergency key to lock or unlock the vehicle .
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Have the SmartKey checked at a qualified specialist workshop.
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Have the SmartKey deactivated at a qualified specialist workshop.
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If necessary, have the mechanical locking mechanism changed as well.
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M Solutions
59
Opening and closing