Leaderboard

Might sounds like a daft question, when you had the fans off/stripped down, did you apply 12v to them and see if they actually spun? From all your diagnostics you sound like you're almost there. I'd be surprised if the ECU wasn't sending a trigger to them. I've also not heard of the fans coming on when the air-con is engaged. I can't say I've ever seen mine on in that situation. (2005 2.8crd so a very close model to yours). On the seat heaters, since circuit seems to be sound, i'd be suspecting the connectors under the seat as i've found these to rattle loose easily. Again, why not disconnect them and stick your multimeter on them when switched to 'on' and see if you get a voltage through which would check everything including the earth bonding to the seats?

I would go to a dealer and get them to operate fan(s) and EGR using diag equipment, at least that rules out the fans/circuit of they work, they can hire the older equipment. If they say they cant or give some excuse then go elsewhere because they clearly cant be bothered.

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