Ac Compressor Clutch

[lexie430]

I bought a used 2002 ls430 a year ago. I've been very happy with it. Although the climate control unmistakably works, the AC compressor clutch does not appear to disengage/engage/cycle/click intermittently. Is this normal? Thanks in advance.

[steve2006]

Hi and welcome to the LOC.

The compressor should cycle on and off when the AC is in use and not be permanently running,although you think the AC is working this would indicate a problem probably due to a low refrigerant level.

Before doing anything else have this checked by a competent AC engineer, the clutches on the compressor do fail but they normally rattle as it breaks down.

I think you can also perform a diagnostics check on the AC system by having the OBDII codes read.

[RDM]

Typically the compressor will only stay fully engaged with the fan speed on HI, and under partial throttle. Any lower fan speed settings and the compressor will cycle on/off, as well as full throttle where it disengages temporarily to reduce drag on the engine. If it's not doing that, have it checked.