Last week I faced a problem with my Mercedes E 250, 2010 model, it was not starting after parking in a shopping mall. Then I started the car after jumping with another Car, mechanic told me my battery is almost dead, so I changed my battery. It was fine for 2 days, there was no issues, but after 2 days, today it is not starting again, unfortunately Jumping is not worked this time, the other car was on running with upto 5 RPM for morethan 7 minutes, but still my car didn't show any sign of starting. Main light and horn are NOT working, but door lights, locking lights, and ambience lights are working, and light on meter showing kilometers is working. Before two days jump starting is worked with old battery, now jump starting is not working with new battery, both attempts are made from same car

 

A couple ways to go. Take your battery to an auto part store and have them do a free charge and load test on the battery. Note you cannot load test a dead battery. If it won't charge or pass the load test you need a new battery.

You could need another battery. If you have another car and that battery from another car that fits you could try that if it starts it means you need a new battery.

Starter?
If you have voltmeter, you can use that on the batter and have someone, try to crank the starter. If the batter voltage does not drop, you know that the starter is not getting electricity to crank.

Follow the directions and connect a remote starter from the positive battery terminal to the right terminal on the starter. Find a YouTube vid or some other online instruction on how to connect it.

Note there may be particular instructions on how to connect the remote starter switch on your particular vehicle as to if the ignition key needs to be on or not.



If your starter cranks normally with the remote starter switch you have an issue in your starter electrical circuit.


A typical thing that causes issue is if you have an automatic transmission and the Neutral Safety Switch goes out your starter won't get the electricity.

If the starter makes no noise and is totally dead, it should be removed and tested.

When the starter on my 84 300D finally died I took it apart and found that the brushes were worn down to a nub and that is why it was no longer working.

 

If your battery was fully charged and if it sits unused for a day or so it could be there is something draining the battery. If it is a diesel sometimes the glow put relay sticks and drains the battery. The generally kills the battery overnight if not sooner.

If a diode inside of the alternator goes bad that can drain your battery but it is slower than the glow plug relay.

Having a voltmeter tells you a lot. One thing it can tell you is when your car finally starts if your alternator is charging the battery.