Hi,
I recently bought a non running 2015 XF2.2, the history of the car seems to be some kind of water damage and the battery was faulty. I've replaced the battery and the dash and screen are now working on first push of the start (all be it with quite a few functions that are unavailable such as audio functions, sat nav and heated seats) but the major issue being as soon as I try to crank the engine everything goes black.

When I connected the car to diagnostics it showed up with 77 DTC codes across various modules and some modules are just not registering as fitted, but most of those codes showed as historical, I saved the list and then reset all codes, of which only 3 showed as permanent (shown on the attachment).

I'm planning on pulling out the seats to access the modules under the seats to look for obvious damage/faults and clean up all connectionsI I bought the car knowing I would be changing many of the modules and get the main ECU sent for service or repair but I'm left with these main questions.

1. Any ideas where I should start to look for the MOST issue?

2.Are there any other places I should be looking for modules other than under the seats?

3.which of the cars modules are addressed to the car and which of them are plug and play so can be just easily replaced with second hand units.

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