2011 Mercedes CL-Class Owner's Manual - Page 376
2011 Mercedes CL-Class Manual
Page 376 highlights
374 Display messages Display messages Possible causes/consequences and M Solutions The KEYLESS-GO key is not in the vehicle. A warning tone also sounds. If the engine is switched off, you can no longer lock the vehicle centrally or start the engine. X Pull over and stop the vehicle safely as soon as possible, paying attention to road and traffic conditions. X Engage the parking brake. X Locate the KEYLESS-GO key. The KEYLESS-GO key is not detected while the engine is running because there is interference from a strong source of radio waves. A warning tone also sounds. X Pull over and stop the vehicle safely as soon as possible, paying attention to road and traffic conditions. X Engage the parking brake. X Operate the vehicle with the KEYLESS-GO key in the ignition lock if necessary. On-board computer and displays  Key Not Detected (red display message)  Key Not Detected (white display message) The KEYLESS-GO key cannot be detected at present. X Change the location of the key with the KEYLESS-GO functions in the vehicle. If the KEYLESS-GO key is still not detected: X Change the location of the key with the KEYLESS-GO functions in the vehicle. X Operate the vehicle with the KEYLESS-GO key in the ignition lock if necessary.  Remove 'Start' Button and Insert Key KEYLESS-GO is temporarily malfunctioning or is defective. X Insert the SmartKey into the ignition lock and turn it to the desired position. X Visit a qualified specialist workshop. At least one door is open. A warning tone also sounds. X Close all doors and lock the vehicle again.  Close Doors to Lock Vehicle