My firebird recently got an engine swap and after my compressor won't
come on. I'm pretty good w/electrical so I checked the wiring diagrams.
1.A/c cruise fuse (under hood)-ok >2.swapped relays to be sure it
wasn't that-ok >3.tested the dk grn/wht wire from the a/c control
switch inside: turn on & get ac-12vlts, off-nada-so that's ok.
if you are facing the car from the front on the same side as the battery? I was
thinking that the guy that installed my engine might have messed up something,
but everything else works. I changed the compressor and found that the old one
works. If I ground the dk grn/wht wire from the rely the compressor kicks on.
Could the PCM be the source of my problems or should I try the wiring first. I
have already tested a fair amount of wires for shorts and they all seem fine so
far, but I haven't been though them all. (Got to Dark) lol.
How do you bypass the a/c temp sensor to check, and the a/c pressure
sensor to check it also?
Here is a link for the wiring diagram:
Any help would be greatly appreciated!
Thanks in advance
Is it possible that during the engine swap the freon was removed? I had to
pull my compressor off during the engine swap on my '88. There isn't enough
length in the hoses to leave the compressor attached to the hoses and get
the engine out. If there is no gas in the system the compressor will not
Oops. Didn't read that you had changed the compressor so you gassed it. You
do know you have to disconnect the battery for 5 min and reconnect it after
the ECM sees a low refrigerant level for a certain period of time, to reset
That would be incorrect.
The LP switch is not wired to the ECM, the ECM controls the compressor and
the LP switch is simply wired to prevent compressor operation should there
be a low charge condition, or the suction pressure drops lower than that
what is required for safe oiling...such as on a winters day in defrost mode.
Motorsforum.com is a website by car enthusiasts for car enthusiasts. It is not affiliated with any of the car or spare part manufacturers or car dealers discussed here.
All logos and trade names are the property of their respective owners.