Hi all. I've got a '93 2 seater jdm targa. Had it for over a year now and I still haven't fixed the air conditioner. I've done a bit of research and from what I can tell i have a short in the compressor clutch. Something about a coil burning out (fair enought she just turned 20). I tested this by whacking in a new fuse and it blows super cold air for 1 to 2 minutes before blowing the fuse and not cooling anymore. What I need to know is the procedure to fix this and what parts I need. I heard you can replace just the coil and do it without removing the compressor from the car. If true can you still buy just the coils? I don't want to have to buy a whole new compressor and get it regassed. Any help is much appreciated zedders.
Normally when the A/C clutch coils burn out they blow the fuse straight away not a couple of minutes later. Once the A/C clutch coils have engaged the clutch, it engages a lower power coil to just hold the clutch in the engaged position, this uses a smaller amount of power. Having said that the fix is the same replace clutch and coils and although I have not done this while the compressor is still installed I have been told it is possible. Dont forget this compressor has been in place for 20yrs so nothing is going to be easy. I have changed the clutch/coil mechanism on the bench. Please give until tomorrow and I will refresh myself on how its done. Watch this space
No, the AC compressor clutches dont do that. Your kinda describing the operation of a starter solenoid in reverse. They are a simple electromagnet with no funky operation at all. Theres a good chance that the coils are damaged somehow and are shorting internally resulting in very high current draw. Confirm this by jumping the clutch wire manually directly off the battery via a decent ammeter. You dont need the car going. Just to rule out a short further up the system. They can be changed on the car with some fair dicking around. Find an old rooted compressor being tossed out and rob it for the coil. You do need a specific puller to get the drive plate off first, then the pulley to get access to the coil. E
As with any inductive type of load youll see an initial inrush spike then settling to *blah* figure. Sorry m8, AC clutches just arent that smart Im afraid!!! E
Thanks for the quick reply guys. Ill run the tests in a few days when I have free time off work and get back with the result
I wonder if the compressor clutch wire is intermittently earthing, eg against the compressor body? Have a close look where the wire disappeares into the front of the compressor. Oh, and too obvious to ask, but I'm going to anyway - what size fuse are you putting in? I just had a quick look at the circuit for the compressor too. The fuse not only supplies power to the compressor, it also powers the coil sides of the radiator fan relay and also the sub fan relay. Note that it is the coil side of these relays, not the power side, so it won't be a fault with the fans themselves. Check all of the wiring to the radiator fan relay and sub relay, and try swapping the relays over with known good ones. It is possible that there is an internal short in one of these relays or the wiring to it, and when the ECU tries to energise the fan in response to the A/C being on, this is what is blowing the fuse. To test this theory, you could also unplug the compressor wire, connect it directly to battery positive via a fuse of the same rating as the one that is blowing, and run the A/C. If the fuse still blows but the compressor is still working, then it's not the compressor. It will be the engine bay wiring or the relays.
