hey all, had a buddy look at my truck and he did the following. jumped the harness for the low pressure switch(one on pass. side fenderwell area) and i started the truck, compressor worked and everything seemed ok(compressor just stayed on and didnt turn off). so i turned the truck off, he told me i was just low on charge because by bypassing the low psi switch it told the computer there was sufficient psi and the compressor could cycle on. with this info, if i understand correctly, my problem has been narrowed down after this test to two possible issues.
1) system is actually low on charge
2) faulty low psi switch
he said it typically wasn't the switch. i topped off my system according to a small gauge that you hook to a can of 134a and that was back in june, all worked well till monday morning (1/28). the gauge i have is just one that you buy at local parts store, small lil 2" gauge that you put the arrow to the green and your good. anyways if i hook the gauge up without a can it should show low if my system is truely low on charge, right?
if i do the above test and the gauge confirms low, i obviously have a leak i guess and need to have it repaired. BUT if the gauge shows adequate charge, should i look into replacing the low psi switch?
few more questions, when i put the gauge on to check, CAN i do it without a can hooked up, and can i do this WITHOUT the compressor cycling(it wont turn on remember..) and get an accurate reading. secondly IF it comes down to the low psi switch, is there a check valve in there that i can just take the sensor out WITHOUT evacuating the system? someone told me theres a checkvalve and the system can be charged when you change the low psi switch.