I had the same problem on my 2002 Export 2.5 CRD...would drive along and the engine would cut out and grind to a halt.
Restart it and it would go for a while then cut out again. No codes posted but I suspected the fuel filter.
This was on a long trip and the problem got worse...when I got to my destination I had a Mechanic friend replace the fuel filter with a new Mopar one I had with me...fixed the problem!
So check you are not getting air into the system or have a clogged filter or bad fuel.
Try swapping over the ASD relay with an identical one next to it.
The 2006 LHD CRDs have a known problem of the Fuel Filter Head Mounting Bracket jamming down on the harness behind it causing shorts to chassis or to other wires.....remove this bracket and check for wire damage in this area.
