Hi when I am in traffic and start stop is doing its thing sometimes it will drain the battery too much to the point where it will not start back up has anyone got any ideas why it is doing it thanks 

Do you still have the original battery fitted?

 

After 4 years of stop/start it will be getting pretty weak - batteries fitted to cars with stop/start usually only have a 3 year warranty for a good reason...

No I have got an aftermarket battery 

7 minutes ago, Marcwolfenden1 said:

No I have got an aftermarket battery 

Did you tell the battery management system that when you fitted the new battery?

 

And is it an EFB or AGM type battery?

6 minutes ago, PetrolDave said:

Did you tell the battery management system that when you fitted the new battery?

 

And is it an EFB or AGM type battery?

No how do you do that and it is just a normal battery 

2 hours ago, PetrolDave said:

Did you tell the battery management system that when you fitted the new battery?

 

And is it an EFB or AGM type battery?

 

1 hour ago, Marcwolfenden1 said:

No how do you do that and it is just a normal battery 

There lies the problem then.

4 hours ago, Marcwolfenden1 said:

No how do you do that and it is just a normal battery 

With a car that has stop/start you MUST fit either an EFB or AGM battery (a "normal" battery cannot cope with the repeated engine starts) AND using a diagnostic tool tell the cars battery management system that you have fitted a new battery.

 

Seems you may have failed on one or both of those steps from your replies.