Things that won't make a/c compressor engage

This is the place to ask questions about your engine components like cams, valves, pistons… just anything that is generally "engine" specific. This also includes questions about exhaust systems such as exhaust manifolds, piping size, mufflers, ect...
Post Reply
Posts: 7
Joined: Thu Mar 06, 2014 9:32 am

Things that won't make a/c compressor engage

Post by Yuyo04Neon » Fri May 09, 2014 7:13 pm

Ever since I bought my 04 neon sxt the a/c hasn't worked and now that the heat is getting strong (I live in fl) I started messing with it and realized the clutch doesn't engage on my compressor so I used a paper clip where the compressor relay goes and stuck it on 87 and 30 to force the clutch to kick in and it worked also my ac started blowing cold air. Now my question is can a bad clutch still engage by doing this technique or does that mean its not the clutch but a sensor, switch, etc.? I know I'm not the best at explaining so if you need me more details feel free to ask. Any help is appreciated, thanks.

User avatar
2GN Member
Posts: 394
Joined: Tue Mar 16, 2010 10:04 pm
Location: Central IL

Post by trojmn » Mon May 12, 2014 1:25 am

its either the relay, low pressure switch (you apparently have enough freon if the air is cold), high pressure switch, or the switch in the cabin.

a) swap the relay with a known working one such as the horn relay.

b) find the low pressure switch on the canister on the passenger side of the firewall. use your paperclip to jump the connector.

c) high pressure switch on the compressor. more of a PITA to deal with but same operation as the low pressure switch, jump connector to test

d) could still be the HVAC switch. Turn it to defrost does it engage then?

otherwise get out your multimeter/test light and start tracing wires.
03 SRT
Now building for GS ;-)

Post Reply

Return to “Engine”