Replacing 1988-1994 XJ6 Climate Control Parts
The Delanair Mk4 climate control system took a massive step forward in terms of electronic sophistication with a microprocessor and servo motors replacing the mass of valves and vacuum hoses used earlier. Ironically the most frequent problem is failure of the 20-pence micro switch at the back of the fan control cutting power to the entire system, but replacement is not hard.
Unlike earlier Jaguar systems most of the components are easily accessible, the ECU and flap motors (which can't stick) screwed to the outside of the casing and the heater matrix incorporating detachable pipes for the first time Ð cutting the replacement time from 16 hours to one. The exception is the evaporator, replacement of which requires the whole casing to be removed from the car.
Most cars were originally charged with the now banned R12 refrigerant. The later R134 gas can be retro-fitted, but this is best done with a new compressor and receiver drier. Alternatively there are several other 'drop in' gasses which are still compatible with the R12 seals and lubricating oil. Do bear in mind that none, not even 134a, will be as effective as R12 and a pinhole leak, commonly from either a corroded condenser or porous hoses, will quickly drop pressure sufficiently to stop the system working completely.
See our Jaguar Parts Store Catalog to order parts.