Hello. Looking for some advice please in troubleshooting a fault when the A/C system is operating on a 2006. When the A/C system is turned on I get a fault (red warning triangle and a P0AA6 code) almost exactly 36 seconds after the system is turned on every time. Any thoughts to fix this issue or what to look at? Thanks - PK
Based on age of the car you'll want to plan a bigger picture approach with all the basic maintenance, checking hybrid system clean up / tune up via reconditioning or alternatively replace the pack with new because A/C can be hard on the battery in super hot weather. Specific to the error code the symptoms for an AC system are best diagnosed by evacuating all the refrigerant with an expensive machine and measuring it, repairing replacing parts, as well as leak down testing, measuring temp&humidity inside system, inside car and as referenced by outside temps, very precise amount of refrigerant & oil back into the restored system, etc.. As in one of the least DIY jobs on a Prius. An expensive machine and someone who uses that machine every day is what my conclusion was when I studied this job in the past.
Could be something as simple as moisture in one of the HV cable connections for the inverter/AC compressor circuit. Could be as crappy as a grounded out AC compressor.
