ok so still got the warning light issues even if I unplug everything from the I bus except the dash and light ecu
so can only think its one of these causing the I bus fault
if I change the light ecu do I need to put the chassis number in and if so can I do this with the iid tool?

If you mean the LCM, from memory most people have just been able to do a straight swap.

Worth having a look inside to check for any physical damage / water ingress etc. It is a little difficult getting the PCB out without destroying the case! .
Experience is the only genuine knowledge, but as time passes, I have forgotten more than I can remember
Volvo V70 P2 2006 2.4 Petrol 170bhp Estate SE
MG Midget Mk1 1962

Previous: L322 Range Rover TDV8 3.6 2008; L322 Range Rover TD6 3.0 2002; P38A Range Rover V8 1999

What about the dash ?

I did try another lcm but no change

But I also changed the dash but that had no effect but have been told that if you don’t put the chassis number in it won’t talk to anything