The PCM supplied by the customer was a slightly earlier revision (111A instead of 111B). Checking the diagram for the earlier car I found that the throttle body is fed from the ignition relay on this version and not a seperate relay.
I didn't realise the customer was sourcing his own part.If I had known I would have given him the part number to buy. So rather than order by part number he must have ordered "ECU for 2001 S-type" or similar on fleabay.
I wired the throttle body power supply to drawing for the earlier module and all works well.