I have a 2008 cx9 the ac compressor want kick on,in fact the relay does nothing when u turn o the ac. I am trying to figure out what’s going on. I put a test light on the two wires going to the compressor while engine is running and ac on but the test light want light up. Now I’m not sure which of the two wires is hot but checked both and nothing. The relay is good as well as the ac fuse and there is power at the relay socket but nothing to the compressor. could this be a problem with the ac switch inside the car or what I’m running out of ideas I don’t want to think bad compressor since there is no power going to it so can someone help me here cause it’s to hot to not have it,thanks in advance.
2008 CX-9 No power to AC compressor
- Thread starter medicman681
- Start date
How do I do that?
There is B+ on the input side but nothing coming out. I jumped pins 30 and 87 with the Freon bottle attached and the compressor kicked on and started blowing cold when I turned the engine off a put the relay back in started the engine turned on the ac nothing, no power to compressor. Could the ac high pressure switch be bad, or perhaps the climate control panel inside the car? I’m stumped as long as I bypass the relay it works and I’ve swapped relays no difference and all fuses are good.
Sorry I am pretty sure it was 85 that had power when motor was running and ac on
Dumb question would I check these two pins with the relay removed?
Will do,
It’s been awhile since I have messed with the ac I took it to a mechanic they advised it was the compressor so I replaced that but still want come on via the inside controls took it to another mechanic the flushed the system and put Freon in it but it still has no power to the compressor. The worked on it couple hours testing several different things which included pulling the center console to access the climate control addy. They ended up jumping something on the back of it and the compressor came on but that’s it. Told me to bring it back and they’d try trace the problem down. Guess my question is could it be the climate control assembly itself, do they go bad
there usually is a pressure sensor on the system, it can be fan related etc. I haven't studied the electrical diagram but there usually is a lot of condition needed for the AC to come on. If all the conditions are met and the AC still doesn't come on but the compressor does when you bypass it, then you might have a unit problem but i doubt this is it. That is a big electrical troubleshooting you need.
So if I start the car turn on the ac then there’s power on slot 86 of the relay when the relay is put in shouldn’t the relay click in and send power to pin 85 which I assume sends power on to the compressor or what. I’m not understanding which pin of the relay sends power on to the compressor
Also,
There is a link here for the workshop manual for the 2008 cx-9 : https://cardiagn.com/2008-mazda-cx-9-grand-touring-service-repair-manual/
If you click on the link for the “symptom troubleshooting (hvac)” section, I believe diagnostic No 9 would be the one that applies to you. You can try to follow it step by step.:
DIAGNOSTIC PROCEDURE NO.9 NO COOL AIR FROM FRONT/REAR VENTS DIAGNOSTIC PROCEDURE
There is a link here for the workshop manual for the 2008 cx-9 : https://cardiagn.com/2008-mazda-cx-9-grand-touring-service-repair-manual/
If you click on the link for the “symptom troubleshooting (hvac)” section, I believe diagnostic No 9 would be the one that applies to you. You can try to follow it step by step.:
DIAGNOSTIC PROCEDURE NO.9 NO COOL AIR FROM FRONT/REAR VENTS DIAGNOSTIC PROCEDURE
