Have Toyota Questions? Ask a Mechanic for Answers ASAP
Hello my name is ***** ***** thank you for allowing me to try and help you. First of all may I ask you a few questions so I can better understand where we are. Did anyone do a performance test on the A/C and what were the pressures on the low and high side?when a/c not running and when running? I need those measurements to go further.
ok this may be difficult with no readings but lets give it a shot if it cycles like that it's an indication of 1-- improper charge (over charge) if low on suction side and over high on pressure side there is a blockage in the pressure side ,usually at the expansion valve, if it's equal on both sides then there is a internal leak in the compressor. all those will contribute to the pressure sensors giving the A/C amplifier the wrong readings to operate.now if all those pressures check out good , then look at the drive belt for slippage and or the RPM sensor on the compressor, all these will trigger your cycling problem. So you see how important reading these pressure with a good gauge or A/C station are. I'm quite surprised who ever charged it didn't do the performance test and check it's operation . hope this helps and good luck.
ok but to make any kind of assessment one needs to know that the basics are tested and up to snuff first, and if the person that charged your system was a A/C expert he would know how to fix it and know the steps it takes to isolate the issues to get to the problem. I never assume things were done right until I either check them myself or get a second opinion. But if you have faith in these things were done correct, then there are three things that can cause a short cycling as you describe and that is the pressure sensing switch and the RPM sensor , these both have inputs to the amplifier which is like a computer so garbage in garbage out as it were. test and replace these items first before you condemn the amplifier cheaper and easier to do. Depending on the type of compressor on you vehicle the RPM sensor may either be internal or external. you can find that out at a dealer if you can read the part number on the compressor or by the vehicle's vin number. if you need further help let me know , good luck.