QuestionAs stated in the question the dash states that the a/c system is very low and the comoreesor is off. The a/c system pressure when checked on a 85 degree day was between 90-100 psi static pressure it went up some while the engine was running. The a/c compressor clutch did not come on even after temporary jumping the low pressure cut out switch. What should be checked next?
AnswerJohn,
The good thing about your system is that it has a self diagnostics system built into it. The bad thing is that it has a vague self diagnostics system built into it.
First, the pressure with the compressor off does not necessarily tell us how much refrigerant is inside the system. If the computer is saying it is, chances are it is.
Ok, first check your fuses, If either of your 2 10A fuses in the underhood fuse block is blown, your compressor will not engage. One provides the relay coil power to energize it, the other is the power source that goes through the relay contacts then to the compressor.
Jumping the low pressure switch will do no good if there is no power going through it.
If both of your fuses are good... here is how you put the system into self-test mode. If you can send me the codes that read out, I can tell you what circuit(s) the fault is affecting.
To enter: turn the ignition on (engine off) and simultaneously press the OFF and WARM buttons on the climate control cluster for three seconds or until a segment check is displayed on the Instrument panel cluster.
A series of codes should begin being displayed, any codes beginning with the letter A are the ones that involve your A/C (I can break down the others also for you if you like) They should read something along the lines of A010H, or A046C, etc.
If you press off on the climate control as the codes are being displayed, it will begin again with the first code.
After it runs all of the codes it has stored, an option will come up to choose individual systems to test. Your choices are ECM, IPC, ACP, and SIR. To scroll between these choices use your fan LO button. To select the system to scan use your blower HI button. And when you have finished, hit the AUTO button to exit the diagnostic mode. Again, I need the codes for the ACP system in particular, but can tell you what the other systems are trying to tell you also.
So before all of this, check your fuses. If they are good, do the self test and let me know what codes come up.
Thank you for the question, I hope I was of some assistance. If I can do anything further during this process, or in the future, please do not hesitate to ask. If you found this response to be of some assistance, please remember to rate this answer. Thanks again and good luck in everything.
