renaul trafic 1.9 dci wont start ?

hi all first posting on here hope some one can help
got a 52 reg renault trafic 1.9 dci van my problem is the van turns over but will not fire up problem started with a major loss of power no go in it at all so ( orange heater plug light came on ) pulled up on m/way & foned the rac
he pluged it into his fault code reader but no codes came up so he took the egr valve out & cleaned it up but no diference at all he advised me to get it into a garage
then the next day when i was very very slowly taking it up to the garage i was at traffic lights & it just cut out & now wont start & the red engine & stop light are now on the garage carnt find the fault so its now sat on my front i have put a new mass air filter on it but no joy
eny ideas would be very helpfull ,,,,, thanks