So I'm pretty sure my A/C amplifier is going bonkers. Starts out fine for a bit then decides I want air conditioner when it's 30 degrees outside. All the servos and flaps seem to work exactly as expected. Just has a mind of it's own lately!!

Sourcing these is a bit of a chore. I'm working with everydayxj to get a used one, but that's for an untested one. Since it's a known failure item, I'd love to snag a new one or close to it.

To date, I've also contacted kwecars in the UK and they indicated "We don not have any replacemen ts sadly, and the demand is so infrequent that it has not justified our designing a replacement. However we used to be able to get a modern replacement from ahoward@british4wd.com in Australia. It would be worth a try with him. If he gets enough inquiries he may dust off the design and make some more...."

No luck from the referral they provided.

I know our cars are old, but being that it's the same part for the xjs, built over so many years, and a common failure item, I'm actually somewhat surprised this part would be "unobtainium".

As Always, THANKS IN ADVANCE!!

 

Never had any real issues with that actual unit.

Getiing it out of its hiding hole is major surgery, and many have simply plugged the replacement into the loom plug and then pushed the thing into whatever space it fits.

My findings with that system have been:

1) Temp rheostat flaky
2) The 2 TINY screws that hold the RH switch pack together need tightening. That tightening is usually only by 2 flats of a hex, and has fixed 3 of my 6 over the years. Radio out, facia off, and SMALL nimble fingers on the backside holding said nuts whilst tightening the front hex. Fun, NOT.
3) The many earth straps on a small stud tucked under the LH footwell snout are loose. RHD easy sort of, LHD, ENJOY.

There have been other things that I forget, but that amp thing has never been one for me.

I dont know anyone here that makes that newer style either.

 

in the USA, John's Cars in Texas sells a revised AC Amplifier for the XJ. I think it was developed in Australia. Dont even bother trying to remove the old amplifier, just disconnect the large round plug -the white plug with many thin wires-, and connect the new one.The new one is shaped like a torpedo. Jaguar conversions, swaps, parts, service and advice - from John's Cars in Dallas.

 

Thanks for the insight. I confirmed John's Cars no longer supply that unit, but do have some working used ones.

I think I should do some more diagnostic work to verify functionality. Were the symptoms of the "flaky" rheostat similar to what I described?

Thanks,
Doug

 

In my xperience I have never replaced the amp. I have replaced the Heater Valve and the Expansion Valve, the latter which means discharging the system, replacing the Dryer-Accumulator, then attaching a Vaccuum Pump, then recharging system again. Big job. Temporary Substitution of the amplifier is the easiest way to go. If the symptom goes away with another amplifier, BINGO! If nada, on to the next part. Are you saying David does not have a used amp?

 

Doug,

The temp rheostat gets a flaky spot where the contacts "sit" for years and years. Sometimes working throughout the scale cleans the thing, sometimes not.

 

I have the Delanaire a/c parts from a 1986 XJ-S V12 Coupe: The Servo, the Blowers Relay, the Amplifier, the Mode switch, the Temp rheostat, and the Vacuum Solenoid. I'll add a picture later.

 

Try David Boger at EverydayXJ.

Everyday XJ

Great guy and great prices too!

 

David has one available, but I have to wait until he can remove it from the car. He can't test them any more as he no longer has a functioning series III.

 

I wonder as to just what function the amplifier performs.
The name implies enhancement. Could it's internal circuitry
be analyzed and duplicated with "off the shelf" electronic'stuff.


Answer: Yes, at least one such device was formerly available.


Question: who on this forum has the will and the skill to do it.
Not me, that is for sure.


Next; I wonder f there is a way to bench test one. In situ testing seems an issue as it is "tucked away" quite well.


Or; A manual method of performing the functions...


Carl

 

Carl, the issue with those amplifiers is that they are encased or encapsulated or whatever you call it, in EPOXY. not friendly to open and duplicate.

 

Oh! A box of Magic! I get that!
And the Magician died! Opps.
(';')