Mercedes W204 C63 AMG 2008 NON Start

Hi guys.
I have a Mercedes C63 AMG 2008 W204, the car is non start and does not crank.
The starter motor relay is clicking like mad and the radiator fan is going crazy.
When i remove the relay fan goes off ignition comes on and steering lock is working finely.
I replaced the relay still same issue... I took the front SAM unit out which also had the relay on it and checked for water damage, all ok, but i cleaned it up and all the plugs tried it again same issue...
I got another SAM unit and fitted that in exact same problem. I have checked all the fuses back and front all ok... I removed the door sill trims to check can plugs under there and kick panels for water damage they are all ok too... Checked all fuses and cables in boot battery area all good...
The car seems to have low voltage added booster on battery and jump leads to front still same...

Fault codes are:

Engine

P2285 undocumented code

374A The internal Data could not be stored in the control unit

P0562 Voltage supply of component motor electronics/battery voltage too low

1106 relay circuit 87 (engine)

Gearbox

C141 no can message from central gateway

C121 no can message from esp

C164 no can message from N22 AAC

C155 No can message from instrument

D402 No can message from ECU

Gateway

U118100 The front end can network management is unstable

I have also checked pilot fuse box on passenger side, any ideas or anyone come across this fault possible ECU?