L322 No communication with air suspension with diagnostics

Good evening all. Just looking for abit of advice...i have a 2004 l322 td6 range rover. When i bought the car a few months back i had the air suspension inactive warning on dash. For some reason unknown to me there was no ecu/module fitted?? I got one for it plugged in and all worked fine but couldnt read it with inpa or icarsoft. Now i have air suspension inactive fault on again but cant read it with diagnostic machine! I have tried un plugging the headlights,light control ecu and still no joy in communicating. Just wondering if anybody has had this issue before and what fixed it and also if anybody has a wiring diagram for the obd socket and suspension module. Its now starting to drive me insane!!
any help would be appreciated

Thanks
Alex.

A lot of modules in the more recent rr's need programming with chassis numbers and mileage. If not, then the newer module may not communicate efficiently.

Mark Piercy said:

A lot of modules in the more recent rr's need programming with chassis numbers and mileage. If not, then the newer module may not communicate efficiently.

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IMO the air suspension ECU doesn't need coding. I borrowed one once for testing and it worked ok, even reported a front crosslink fault as mine doesn't have one. Not familiar with inpa or icarsoft so I can't help there.

backinblack said:

IMO the air suspension ECU doesn't need coding. I borrowed one once for testing and it worked ok, even reported a front crosslink fault as mine doesn't have one. Not familiar with inpa or icarsoft so I can't help there.

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This is why I won't go no further than my 38, I deal with this **** all the time and don't want to do this with my own car....