Automotive Air Conditioning Information Forum

System is down to 30psi so the compressor does not come on, how do you add dye to the system to check for leaks? Do I need to jumper the compressor?

Is it shut down do to low refrigerant or do you have an electrical issue?

Low pressure, static is 30psi.

I'm surprised that you didn't notice lack of cooling when the system was low on refrigerant but still enough in it to engage the compressor.

I have a 2004 Frontier that was low on refrigerant, poor cooling (Arizona) and low pressures on the high side. I've had this 5.5 years, and believe that there had never been any AC service ever before. So I bought a can of R134a that contained UV dye (make sure there's NO SEALERS in it, never use any sealers); note that the dye tends to settle in the can (there's no oil in the can), so instructions state to add with the can upside down. Note that in my instance that the compressor was still running, my guess was that in 13 years a little refrigerant had leaked out. So I attached the can to my gauge set, bled out any air from the hoses/attached to the service ports, and with the engine OFF held the can upside down and higher than the gauges, and opened up the valves to let the can contents enter, as the can pressure was higher than the static pressure in the AC system. AC has worked fine for last 2 months.

Remember: if you add as liquid (upside down can) with the system running, one must be careful and patient to add liquid refrigerant slowly so no damage is done.

I also have a 1998 Frontier with 218K (mine since 100K) with same AC system, believe that system was also intact at the time; but about 5 years ago I did add about 6 oz. R134a to it (no dye) and that has run fine since. So I think both my Frontiers had lost some refrigerant through normal attrition over the years.