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Well it finally happened. With 124K, no AC on our 2010. I put a charger on the Low side and it showed 0 pressure. Now I would prefer to just see how long a charge will get me if there is a small leak in the system. The Chilton manual is worthless in identifying the switch plug and which wires to jump to spin the pump. I have a guess that its the plug on the High pressure line that is next to the "window" in the line but that plug has 3 wires on it and no where on the net can I find the answer to what should be a rudimentary question so here I am. Can anyone point out exactly the 2 wire pins that need the jumper?
 

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I have a guess that its the plug on the High pressure line that is next to the "window" in the line but that plug has 3 wires on it and no where on the net can I find the answer to what should be a rudimentary question so here I am. Can anyone point out exactly the 2 wire pins that need the jumper?
If the connector you are looking at has a Black, Green, and Blue wire, then you are looking at the correct connector. The problem is that this pressure switch isn't a simple on/off switch.

Power is supplied on the black wire, and it should have 4.5 - 5.5 volts when the ignition is turned on. The green wire is ground. The blue wire has a variable output depending on the pressure in the system. It is working like a TPS sensor (if you are familiar with their operation).

If the voltage on the blue wire is 4.74 volts or higher, the refrigerant pressure is abnormally high (more than 455 PSI).

If the voltage on the blue wire is below .76 volts, then the refrigerant pressure is abnormally low (less than 28 PSI).

So connecting the blue wire to either power or ground will disable the system. You might be able to connect a resistor between the black wire and blue wire to reduce the supply voltage to something between .76v and 4.74V. Since the current draw through the blue wire is unknown I cannot predict the value of the resistor. It will be a matter of trial and error.

On the other hand, you should be able to add enough refrigerant without the compressor running to bring the pressure above the minimum 28 PSI requirement.
 

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OK, that clears this entire mess up! I tried to put pressure in the low side with a relatively new can to no avail. I'll get a brand new can and try it one more time, if that doesn't break over the 28 psi low value, its off to a shop. Thanks for posting the details! After a lengthy search, know you are the first to clear up this "paper clip/jumper wire" speak of the Chilton and various google hits.
Be Well
 

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You do know the trick of putting the can of Freon in hot water don't you?
 

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The resistor trick should be a safe procedure to fool the system. It has been used in the past in what is now known as the "Dr. Dyno 3.3 K-ohm TPMS Warning Light Elimination Technique".
 

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You do know the trick of putting the can of Freon in hot water don't you?

I'v read about a hot towel but not that. Good tip tho.
Now I put a new gauge / can on it and it actualy had way too much pressure in it according to the can gauge so I let some out with the faulty gauge line I first tested it with. Problem is, it still won't turn the pump on. The 15A fuse is good, the AC light light when on, blower works well. I'm thinking it may be the pump relay as it was mentioned they go bad all the time and to swap in the horn relay to test but here again, both fuse panels under the hood have no relays marked AC or Horn for that matter. And again the Chilton is toilet paper. Any ideas?
 

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Now I put a new gauge / can on it and it actualy had way too much pressure in it according to the can gauge so I let some out with the faulty gauge line I first tested it with. Problem is, it still won't turn the pump on. The 15A fuse is good, the AC light light when on, blower works well. I'm thinking it may be the pump relay
Only the V6 RAV4 has the traditional magnetic clutch which is controlled by a relay. The I4 compressor is turning all the time, but the displacement of the pump is controlled by a signal from the "A/C Amplifier".

The compressor has a plastic break-away pulley to protect the drive belt if the compressor should lock up. See page BE-34 of this document.

If you can see the pulley turning, but the hub of the compressor is not turning (like a traditional compressor would appear with the clutch disengaged), then maybe the break-away pulley has broken away.
 

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Only the V6 RAV4 has the traditional magnetic clutch which is controlled by a relay. The I4 compressor is turning all the time, but the displacement of the pump is controlled by a signal from the "A/C Amplifier".

The compressor has a plastic break-away pulley to protect the drive belt if the compressor should lock up. See page BE-34 of this document.

If you can see the pulley turning, but the hub of the compressor is not turning (like a traditional compressor would appear with the clutch disengaged), then maybe the break-away pulley has broken away.

Thanks for posting that link. Its super informative. My pump shaft is spinning but the info their refers to a solenoid that controls the variable pump out put. I guess that would be another inspection of this solenoid failing there on the pump. It also states the Yoda should have tripped a DTC on any of the individual sensors.
I guess I'm done with this. Time to pick up the phone tomorrow and make an appointment. Here it is. A pumping pump with good pressure that makes no cold air. Once the dealer gets done with me, what will be the $$$ savings over a simple conventional system that could be repaired by a shade tree owner? We will see. Thanks a bunch to every one who responded.
 

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If you can reach the connector on the compressor (a gray wire and a Brown wire) you can do some basic tests. If you measure the resistance of the compressor side of the connection it should be 10.1 to 11.1 ohms. If it is not, replace the compressor and pulley.

The voltage on the cable coming from the A/C amplifier is a pulse wave pattern that changes it's width depending on the amount of cooling required. So there is not a fixed voltage to look for. Still, if you checked for voltage on the cable and saw anything at all you could probably eliminate a short or open in the harness as being the problem.
 

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If you can reach the connector on the compressor (a gray wire and a Brown wire) you can do some basic tests. If you measure the resistance of the compressor side of the connection it should be 10.1 to 11.1 ohms. If it is not, replace the compressor and pulley.

The voltage on the cable coming from the A/C amplifier is a pulse wave pattern that changes it's width depending on the amount of cooling required. So there is not a fixed voltage to look for. Still, if you checked for voltage on the cable and saw anything at all you could probably eliminate a short or open in the harness as being the problem.

Thanks, You have been extremely helpful in helping me find the point of giving up! When I was young, swaping out v8's & switching tranies was called a good time. But nowa days, if one more fleck of crap falls past my bifocals & into my eye while I'm wrenching on my back, I'm bound to just 12g the mess and go buy another clunker with 12v switches.
Be Well
 

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I had the Yota at the Dealer today and realized that the OBD can not detect a bad AC compressor. At first they told me it was low on pressure so it only needed a charge. An hour latter the guy comes out and says its a seized compressor and to fix it with a new OEM pump would cost me over $1200 ($799 pump). It took them 2.5 hours to figure that out. So I told him no thanks and to button it up and I'll be on my way with a $106.46 bill. So there you have it. 124K on the AC pump and its toast. Apparently the AC pump shaft is not directly connected to the center pulley clutch shaft bolt that is spinning with the pulley. I would love to tear this pump of mine down to see exactly what the issue actually is. The pump made no noise at all and worked perfectly last fall. I would be more inclined to think it was electrical such as the variable flow solenoid. According to Rickl's kindly supplied documents, this solenoid is what allows the system to load pressure on and off the pump depending on sensory input of cabin temp and engine rpm to name a couple of the input values. On the other hand, can the pump shaft bearings be so marginal that it was imperative they design the pump with a break away pulley clutch in case of shaft seizure ? Well, what ever the cause, I find my self at the point of trying to locate a decent deal on a pump. Any one out there know of a decent supplier of rebuilds? I'd go low mileage used but I cant seem to trust mileage figures from these used outfits.
 
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