I am looking at converting from the old aircon system to the digital climate conreol. As far as I can tell I need the panel and two servo motors for the distribution and the recirc. Along with some extra wireing of course! has anyone else done this?

Stewart

Hi Stewart

There is also a sensor fitted on the heater pipe and another one into the passenger side of the aircon condenser housing. I also suspect there is a risk that your main ECU will not contain the routines to automatically control the air conditioning. The early cars (first couple of years build) had only a simple non automatic form of airconditioning and an upgrade to those could be very difficult.

Regards

XMexc

These may already be there, what my car has is a crude form of climate, although not digital it is temp controled (has the cabin temp sensor by the cabin lights)

Stewart

Hi George

I suspect that XM ECU's for a particular engine type are interchangable. The risk comes that if you get a spare one from a car made at a much earlier date it may not support all the equipment to your later car. In the same way if you want to add an ECU controlled function to a car then the chances of success are much higher if that particular function was being supplied on other models with the same engine built at that time.

Regards

XMexc

Hi Stewart

I have never come across and XM without the roof light sensor. I have some recovered aircon boxes from various types of A/C XM's and will have a look at them to see what more I can tell you about the differences. I seem to recall that one motor drive is present in all A/C cars and that the lever on the drivers side of the box is wire worked in the simple A/C.

Regards

XMexc

From past experinces of similar projects on other cars (although not XMs)

The temp sensor in the cooling system is normally present on all AC cars, or it should be as this is so the system can shutdown should the coolant get too hot (thereby reducing load and hopfully allowing the temp to drop, only really happens in places like Saudi while towing a caraven up a steep hill, but does help should you run low on water) the one on the evaporator is to do the reverse! (if the system has reached -10 then continuing to run the compresor is doing nothing more than using fuel!). The ECU's only interaction normally is to raise the idle to compesate for the extra drag of the AC compressor. The control panel normally does the rest, I've yet to see an engine management system that has any of the AC functions in it

Stewart