Need AC help

Hello all, new here. My name is Wes. I am working on a 2007 Toyota Tundra SR5, 5.7L.

I have replaced the A/C compressor, condenser, and expansion valve. I put a vacuum on the system for about 3 hours. Then checked to be sure vacuum would hold. Put the correct amount of oil and R134a in, and replaced the magnetic clutch relay.

When I was charging the system the compressor would kick on for about 2 to 3 seconds the turn off. The ac light would start to flash. So I put a jumper in the relay so the compressor would continue to run so I can finish charging it. Now that it is completely charged and I put the relay back in the pump does not turn on at all and the ac light stays on for about 2 seconds then flashes. Any help with this will be very greatful. Thank you!

 

Forgot to add that I have checked all fuses.

 

I didn't replace any lines, I wasn't aware of any filters. I'll take a look. I did however blow the lines out before I reassembled it.

 

Hmm, my first inclination would be to tell you that the relay could be the issue; however you already mentioned it still happens when you have jumped it. I have had issues with my relays on several occasions, if you had a spare one around, might consider checking that.

Also, I am not sure if this has any validity, when I brought my truck to the AC repair shop, they told me that there was a sensor that often goes out, which can create issues. The 'sensor' is supposed to check the pressure of the lines and if it exceeds a certain threshold, it will purge excess refrigerant or not allow the compressor to engage. Again I am not sure if the sensor is a 'real thing' or not.

 

I know their is a pressure relief on the pump and a high pressure switch other than that I don't know. I'm at a loss here.

 

I don't remember pulling out a 3rd plug on the a/c amplifier but is there suppose to be one?

 

Sounds like relay, either that or its over or under charged. Light is flashing because system saw a problem and shut down a/c

 

I replaced the relay still not working. I put a jumper wire in and tha pump will turn on. It is about 80 degrees F. The low pressure side reads 30psi, the night side reads about 280psi. What is the correct reading supposed to be?

 

Again, this is what I've done.
New compressor
New condenser
New expansion valve
New relay
Checked all fuses
Put a vacuum on system and it held.
Put 22oz of r134a in
The only way I could recharge the system was to jump the clutch relay so the compressor would run.

 

I know it’s an old thread but did you figure out what the issue was? Got the same shit going on right now

 

Hey Physco White Tundra
Did you get your issues resolved? I am also having same issue. Or anybody else, what terminals do I jump out, to engage clutch to charge system?

 

Double check to make sure the blower motor is running correctly or the compressor will run for a few seconds then shut off. That’s what my problem was. Three of my others 4 Toyota’s were mag clutch relays.

 

Sorry for the late response. You’re gonna connect a jumper wire from the positive on the battery to the #3 slot where the relay plugs in. Make sure the truck is running and a/c is on high before you jump the compressor

 

After replacing the expansion valve I charged the system and my luck would have it my clutch is froze so now I’m waiting for a rebuild kit.

 

I'm having the same issue people have been telling me it's the AC amplifier not sending a signal to the relay I don't know if I believe that because it's a $500 try. Just let me know what you find out at that third plug on the AC amplifier don't remember unplugging it should there be something there?

 

My issue ended up being the expansion valve. It’s located above the accelerator pedal to the right. Also is this in the pic what you’re asking about

 

I never said you AC amplifier was bad, I said it is not happy with something in the system. Hence why the green light is flashing meaning it has a DTC stored inside of it.

There is no 3rd connector on the amp, only the two shown in the photo.

You jumping the relay makes the AC work but you doing this is bypasses the AC amplifiers job of closing the relay. It is not closing the relay because it sees something else wrong with the system. The orange wire is the trigger from the AC amp to the relay. The AC amp grounds this wire to energize the coil and close the relay. With the relay closed the clutch on the AC compressor is engaged.

You simply need to find out why you AC amplifier is not happy, not just replace it. A brand new one would do the same thing.

The computer is your friend, use it to read the codes in the AC amp so you understand what it sees as wrong. Without this info you are just guessing really.

For reference this is a pretty good list of potential DTCs in the AC amp. https://share.qclt.com/丰田Toyota RAV...utomatic Air Conditioning System)/0420015.pdf

It could be a sensor issue, a servo issue, a communication issue or many other things. Understanding what the ecu thinks is wrong really narrows it down as to where you go look for issues.