Tacoma 2013 AC troubleshooting (tried just about everything)

I’ve been troubleshooting my AC for a couple of days now on my Tacoma 2013 (access cab) and am looking for a bit more input. The main problem is the clutch only kicks in for a couple of seconds after turning on the vehicle and then stops, I get the blinking AC light, and every time I turn the ac off and back on it runs for a few secs again before cutting out.


What I’ve already checked using the information from the lovely people on this forum:
- first I recharged the system with r134a
- magnetic clutch relay with DMM - good
- clutch not seized up at all & freely moves by hand when vehicle turned off - good
- magnet engages in clutch when I put power to it and I CANT move it by hand - good
- grounds on compressor is secured
- clutch coil resistance is good
- pressure switch (2nd gens have a high AND low pressure switch in one) electrical connection is good (has voltage)
- pressure switch itself has continuity so it should be in the appropriate closed position to allow for refrigerant flow (I think)
-jump started the magnetic clutch relay to force the clutch to continuously engage but STILL no cold air

Funny thing is up until now I thought for sure the problem was the clutch itself not engaging constantly, and I thought it was a problem with the clutch speed sensor, but after forcing the clutch to engage continuously with a paper clip I still had no cold air. ALSO - I just hooked up the manifold again to see if the pressures moved at all while forcing the clutch to go but I still ONLY have low side pressure (the high side pressure has always been equal to low side which I THINK means that the refrigerant hasn’t actually circulated fully through the system right?)

And finally, the last thing I tried was to give the system a little more charge to try and get the refrigerant to circulate (currently at 90 psi low side which I KNOW is very high instead of the usual ~75psi when stagnant but I figured once it engages the pressures would fall as it equalizes through the system).

At this point I know I’m probably going to have to go to a shop but I would like to know exactly what needs to be done if at all possible so I don’t get the standard quote for $2000 from the dealership telling me the whole system needs to be replaced. Much appreciated.

 

Pressure reading while running? Both sides?

 

Both sides at about 90 psi while running, even with the clutch hotwired to run comtinuously. I was thinking could it be a blockage in the system? Especially if the pressure switch is closed as it should be (has continuity with DMM)?

 

If the compressor is running and the pressures stay equalized the compressor has failed.

 

Does this HVAC use an expansion valve. You should be have +-30PSI low side and +-125PSI hi side. Could be a stuck expansion valve. And have you properly recovered and vacuumed down the system before a proper recharge? That is very important.

 

Thanks Dm93, that makes sense.

The only other thing I am wondering is what if the gauge isn’t actually letting enough of the refrigerant into the vehicle because it’s not properly pressing down on the Schaefer valves? I only ask because one of the reviews on this particular gauge mentioned something similar. And out of curiosity I just detached the gauge from the truck and then let the refrigerant valve open to see what the pressure of the can itself is and it’s pretty high at about 70…. Not quite the same though so maybe that’s too far fetched

 

You typically will see your gauges move when you connect them to match the pressure in the system.

 

Agree with Dm93 - the pressure shouldn't be the same on both sides with the compressor running, otherwise there would be no such thing as a "high side" and "low side."

 

I’m not sure about the expansion valve. And yep those are the pressures I’m dying to see but just no luck getting there.

Yeah absolutely I know I should have done a proper vacuum with but I just don’t have the cash to dish out right now so I was hoping I could DIY! I get that I definitely can’t know for sure what’s the issue without the vacuum first though

 

Yes it is an expansion valve system but the compressor should still pump regardless of whether or not the system was properly vacuumed before charging, it just wouldn't cool properly.

 

thanks both. Any other diagnostic suggestions I can do or do I just accept at this point I should just leave it/send it to dealership when I can?

 

Bad A/C amplifier?


https://www.tacomaworld.com/threads/a-c-amplifier-help.624522/

 

Well, it starts will a proper charge proceedure for sure to diag with out wasting time or $$ in the long run. The expansion valve act as a pressure regulator sort of between the two sides mush like the old orfice style systems. I am a Toyota owner but Chrysler, jeep, dodge tech.


https://www.tacomaworld.com/threads/help-ac-expansion-valve-2008-taco.435192/

 

I mean if the compresor shaft is spinning and your certain your gauges are connected properly but there's no pressure change then at a minimum it needs a compressor, if there's metal contamination then the condenser and expansion valve and screen need to be replaced and the lines and evaporator flushed thoroughly.
In some cases the metal gets into the evaporator and it needs to be replaced as well.

 

this is also on my list but from what I’ve read I didn’t see a way to diagnose it being problematic other than just straight up buying a new one and switching it out? I wonder if I could just test with DMM somehow to see if it’s working as intended?

 

Also can I just say I’m pretty shocked at how much feedback I’m getting in a matter of minutes from so many people. Thanks so much. This forum rocks

 

It may be as simple as the compressor being bad, since it appears it's not pumping there's no telling how it failed internally so the speed sensor my not be reading the compressor speed and thus the A/C amplifier will shut it down.

 

If you trying to do all this pressure testing and filling with the cheapo cans than that could be your issue. The gauges are VERY inaccurate and you can easily over fill the system. Those cans are good for a temporary top off and that's it. You can make things way worse by continually overfilling the system.

Save the time and headaches and just have the AC evac and recharged the right way.

 

I may just try to find another amp from a scrap yard to swap out and see what happens. Otherwise I’m not sure how else I can tell what the issue is without taking it all apart !!

 

bring it to a shop and have it hooked up to an AC machine. It will rule out like 90% of your potential issues you think you have.