HEVAC not accessible by T4

Goodnight all,

Yesterday I did my by-weekly drive to grab my DSE from the mechanic doh::doh and I kindly asked him to connect it to his T4, to check the faults on the HEVAC, since it was showing the dread book sign.
The T4 wouldn't connect to the HEVAC system as it always showed a communication failed error. Other systems were fine, as we checked the engine and did some cruise control tests.
My mechanic says this either means that the HEVAC is knackered or that the BECM is on it's way out

Some advice please ?

PS - The HEVAC works fine except for not blowing hot air from the passenger's side..

T4 has not had any connectivity issuses with LP Hevac ecu's apart from getting live data responses when viewing live data - it seems to vary between ecu's.The Valeo quality control seems a bit variable....
If you can access other ecu's around the car then I would suggest you do a feed and earth check on the Hevac ecu.Despite what various companies/salespeople say T4 will happily communicate with just about any LR/Rover/MG ecu up to 2005.5 - reliably.Dont worry about the BECM - its fine.