Landrover no engine comms

Hi Guys,

I work for a break down company and keep seeing lots of Evoque and RR stuck in the middle of the road completely lost comms with ECM - no faults in any module apart from transmission saying no comms with engine and unable to connect to ECM!

Anyone seen this?

Hoping for something simple as i've had one towed to me to sort out now and dont really want to go start going through ECM wiring!