Q: Mercedes 2006 R350 not starting.the vehicle was not started for 20 days.road side assistance visited and they said battery is good

Hello, thank you for writing in. In addition to checking the battery, you will want to make sure the battery cables are clean, dry, and tight. When the cables or ground connections are loose or corroded, they are likely going to be able to carry some electricity, but possibly not enough to start the vehicle. You will then want to turn your attention to the "wait briefly" message appearing. This is telling you the vehicle (which runs tests as you turn the key), has detected an issue and doesn’t want to start the vehicle until its addressed. Check both ends of the vehicle and see if the suspension system (which is one system which will prevent starting) is lower than usual. The other way to see what the issue is would be to scan the vehicle for codes and see what sensor is turning on the warning message. For more help with this diagnostic testing, contact our service department to schedule a house call.