So out of nowhere my car throws the SES light and code: P0646 A/C Clutch Relay Control Circuit Low.

I searched and I can't really find a good definition of what to check for this, but I know my A/C was acting up at one point, the A/C clutch felt "grabby" when I tried to use it earlier this year, and now there's nothing, I don't feel the system engage/bog down at all, no cold air, nothing.

Could it be a fuse/relay? Could my compressor have died?

Thanks.

 

It sounds like the ECM signaled the compressor clutch relay, in response to the AC being switched to on, and the relay didn't close. The relay is located in your engine fuse box. That's what I'd look at first. But if the relay is closing, it should be sending 12 volts to your compressor clutch, so your compressor clutch is possibly failing. You could next try supplying 12v directly to the compressor clutch to see if it engages. With the engine on. Watch yr fingers.

 

Ok, I'll do some poking around. I should be able to hear the relay close when I switch the A/C on, right? Man, A/C compressor's are expensive!! Is there an A/C delete mod? =)

 

I don't really know if the relay click is audible. I'd check it on mine but I'd have to reinstall my battery and subframe. Since the engine has to be on, you might only be able to hear it with a stethoscope. You could also pull the connector from the clutch and use a volt meter or just a test light to see if the relay sends power down there when it's supposed to.

And...
http://www.waymotorworks.com/a-c-delete-pulley.html

 

Good info, maybe a bit too technical and over my head, but good info in case I find a friend willing to help nonetheless. Thank you.

And thanks for the link, good to have also.