Power Fc Controlling The Air Con ,, Any Known Issues ?

[cobbadan]

I've had the 33 at the auto lecks all day today trying to fix an air con problem.

What's happening is, it will get cold, then not cold, couple o minutes later its cold again for a little while, then not.

Its been gassed and had a few things tested. What he came up with is that the problem may be in the power fc.

From what i gather

The climate control unit sends the air con request to the ecu and the ecu sends the word out to the relays/compressor etc

All the bits after the ecu seem to be working properly, the climate control unit seems to be working properly, so he thinks it will be a problem in the ecu.

Does this sound familiar to anyone, common issue ?

I was planning to book it in to get the tune checked anyway so i would assume the tuner (probably EFI who was recommended by ERD) would be able to access that kind of info to see whether the FC is doing what it should.

One other angle i was thinking about was, i have the stock ecu. would it be a simple case of unplug the power fc, plug in the stock ecu and see what happened with the air con. or would i lose the tune and/or cause problems.

[cobbadan]

A bit of history.

The power fc has been in the car for about six years.

I've owned the car for about two months.

The previous owner said the air con had been playing up for about the last two years but it never really bothered him so he didn't get it looked at.

[Macross]

Definately not a common issue, unfortunately I can't point you towards where the problem may lie, but I can tell you my current GTR, my previous supra and several friends who all have powerfc's in their car have had no problems at all with aircon control on powerfc (unless of course, it was not setup correctly by the tuner).

[cobbadan]

Cheers macross & jiffo via pm

some other tidbits

The power to the compressor is actually switching itself on and off at random which is why the coldness comes n goes.

It may be an earthing issue, the lecky was saying that the ecu provides the earth to the circuit.

I don't drive it very often but when i do, i'll try to see if there is any pattern to it turning on & off.

will try to get it to the tuner in the next couple o weeks.