Something draining battery?

[RobA66]

This is my first post so apologies!
I’ve been having a reoccurring issue with the engine not turning over on my 2009 Mercedes sprinter van - it just clicks. I’m guessing something is draining the battery as jump starting it works. In the last two months however I’ve had the battery, alternator and starter motor changed. I’ve also taken out the tachograph, the rear camera, unplugged everything from the cigarette lighters and taken out the radio / CD player however the problem persists. Any ideas would be greatly appreciated as I am now stuck for what else it could be!

 

[noogieman]

You have to go through every fuse and remove them one by one to see where the drain stops.
It will take some time to find the culprit.

 

[Deadly Dave]

You could swap a low wattage bulb instead of a fuse for testing, you will need to solder up some leads for this. If the bulb glows then that circuit is drawing power.

 

[Delderek]

Has it got a Tracker fitted? If the internal battery fails it will constantly be drawing power from the car battery.

 

[noogieman]

you could measure drain with an multimeter