1 Attachment(s)
Disconnect and connect the A/C clutch electrical connector.
The title line above, I found in the LR instructions for both installing and removing the air conditioner compressor. This suggests that there is an Air Conditioner pulley clutch, hence power from somewhere must go to the clutch.
I have attached the high line AC electrical drawings and while I can see nothing regarding an Air Conditioner Pulley Clutch, I think that there must be one.
On AC systems that I am familiar with, the compressor pulley has an internal electric clutch and that is what the ECONO switch is sort of connected to. Pushing ECONO disengages the compressor from the engine belts so to speak, and hence engine loading decreases.
While the wiring diagrams does not suggest an Air Conditioner pulley clutch, I think it is there. In any case, something somewhere should shut the compressor down when the AC is not required.
As such, if your system just quit, even though I can only find one reference to a clutch, perhaps the electric power to the clutch has quit, or the clutch if it exists, has quit. I have had to replace same on my GM vehicles in the past and I cannot see this being much different. Maybe others know better.
Re the pdf below, I can find reference to the ECONO button in the Automatic Temperature Control display, (ATC), and Engine Control Module, (ECM), but not the AC compressor or a pulley clutch, but there are references to refrigerant solenoids.
Whenever I see the ECM tied into a circuit, that tends to involve the Can Bus and who knows what it does. My guess is that there is an AC pulley clutch and it is controlled by the ECM and hence does not show directly in the AC electrical wiring - nor can I find any fuse that seems to relate to the clutch either, but there must be something, fuseable link or whatever, somewhere.
so that is why there is no clicking sound
Quote:
Originally Posted by
Davehoos
The compressor described is a late model denso, delphi, zexell or sanden compressor.
These run constantly and change the swash plate stoke, like the old industrial unloading systems.
To save a few dollars, there is no electric coil or compressor clutch.
Later cars have a plastic pulley. A plate replaces the friction clutch; in the centre is a die cast or plastic nut. This has a breakaway section to shear off in the case of compressor issues. Inside, it has a rubber drive to reduce noise. Remanufactures have these but the dealer don't. Had to make these plates for Benz cars and most of these compressors are now made in China.
Not uncommon for the plate to shear off just from vibrant driving.
The original version had a aneroid in the rear of the compressor to control the a/c at set temp. Hot water is used to climate control the vehicle.
Later versions has a duty cycle solenoid to control the temp and economy mode. Turned off, these run at 10% to circulate oil. Most of these can be direct connected to power to get 100% and then pressure switched.
That explains why there is no clicking sound from the compressor clutch as there now is none.
I see on the electrical pdf, a refrigerant solenoid valve, D332, so as you referenced, that must be what turns the compressor on and off, (so to speak). I see that there appears to be three variations of the solenoid valve depending upon the engine, diesel, V6, or V8.
Thanks for your comments re the 10% rate. The old style used to cycle when the defroster was turned on just to make certain oil circulated in the winter months. I wondered just what my AC compressor was doing in the winter as I never would hear any sounds. That explains it.
Not just a fridge on wheels then.
Quote:
Originally Posted by
Davehoos
In Australia we use the defrost with fresh air to defog. The compressor won't engage until the vent temp reaches the 0-5 deg mark. So in effect you need the heater going to get the ac to work.
The Jeep Wrangler owners manual shows a wire being moved for winterization; after study of the picture I worked out it was unplugging the comp over heat switch and disconnected the comp. I was fitting an aftermarket unit that had no off switch.
A problem with cold climates is the a/c suction side becomes liquid and the compressor oil goes solid. Often you only want the compressor to work unless the engine bay is hot. As the systems get smaller the chance of flooding increases. Most of the old accumulator systems the gas volume was simply stored in a chamber as a safety space.
To overcome a hydraulic locked compressor, often the old compressors engage on crank over, and lots of Australian cars had a relay connected to the reverse.
The Toyota Hilux turns the compressor on twice after startup. My Falcon has a pressure transducer same as in the US Fords. If the pressure don't change to the preset amount, the compressor code is set and can't be turned on.
After reading the above, keeping a Land Rover air suspension system operational would be easy for you.
Relative to air conditioning, our Land Rover air suspension compressor is simple. At least the compressor only has to deal with a gas, not both a gas and a liquid; leaks do not matter all that much, and air temperature does not really affect its operation significantly either.
I did not realize that there were all these complications to automobile AC. I thought it was just putting a fridge on wheels - wrong again.
