kyoo

iTrader: (29)

Recently discovered the AC is broken. The switches inside and cables seem to be working fine, but the AC just doesn't turn on. The belt looks okay etc., it just literally doesn't turn on. Normally when the compressor turns on you feel/hear that draw on the motor, maybe a slightly musty smell.. no change at all from on and off.

Any ideas? Could the compressor just be "broken"?

rival879

iTrader: (2)

Just to eliminate some possibilities, does the light on the switch come on? Does the fan blow on settings 1, 2, or 3? In one case, my A/C switch (compressor side) was bad and my mechanic replaced it. In another case, my blower motor resistor failed, and my A/C wouldn't work unless the fan was blowing on speed 4.

kyoo

iTrader: (29)

Thanks for the tips. The light on the switch does come on. The fan itself does work, but I don't know that I've experimented with settings with it in conjunction with the AC. The AC light also goes on when I turn the temp setting to max ac, so like I said I don't think it's the switches/cables. It may be the compressor is bad and needs to be replaced, I guess it's hard to say at this point. How would I know without actually replacing it?

1UpMoto

iTrader: (14)

is the compressor clutch engaging?

kyoo

iTrader: (29)

doesn't seem like it. i had a friend watch the engine bay as i turned the ac on and off from inside - no discernible change whatsoever between on and off.

1UpMoto

iTrader: (14)

you can look at the compressor and see if the clutch is engaging. if its not try jumping your ac pressure switch and see if it kicks on

barneyb

One possibility is that the system has a leak. The compressor clutch is inline with the pressure switch and when the pressure switch is open the clutch will not energize. This is to prevent damage to the compressor which is cooled and lubricated by circulating refrigerant.

If you live where A/C is needed often the clutch be may energizing but not engaging. The clutch wears, there is a specified gap in the service manual for the clutch and as it wears it becomes larger. There's a shim kit available from Mitsubishi one can use to change the gap or owners in some cases have just removed the existing shim and this fixed the problem. In other cases, a new clutch was required.

Behind the clutch is the coil that produces the magnetic field that engages the clutch. If power is reaching the clutch but nothing is happening the coil may be open.

laramie_05MR

iTrader: (20)

If you trust yourself enough with a rubber mallet you can remove the splash shield in front of the compressor and quickly tap once on the face of the clutch with the engine running and the AC on. That will close the gap between the clutch and compressor pulley. If that works use this part number MR315936 compressor clutch shim kit.

kyoo

iTrader: (29)

nothing engaging or changing. what is the ac pressure switch?

How can I look at any of this? Should I pull the compressor entirely? Does the clutch come with the compressor?

I can definitely take a look.. damn though I just spent yesterday adjusting the LICP and had the shield off for that

Cal City Evo

iTrader: (13)

If you have a leak there is a low pressure switch that will prevent the compressor from coming on. I would guess you have a leak and need to find it fix it then have a vacuum pulled and recharge the system.

kyoo

iTrader: (29)

updated with a video - system just not turning on - in the video the ac is being turned on and off from the inside at 5s intervals, off 5s, on 5s, etc. nothing seems to change. suggestions?

laramie_05MR

iTrader: (20)

Did you tap on the compressor clutch face? It is hard to see how big the gap is in the video.

kyoo

iTrader: (29)

i did tap on it. i THINK there is a slight difference between when on and off but I can't really tell too much. Will give removing the clutch a shot today.

Question - with the electrical on but NOT the motor, will the AC clutch move when you turn on the AC? Obviously the belt's not turning so the AC won't turn on, but thought it might be easier to see the clutch position that way. If it's moving but not close enough, it's probably the shim - if it's not moving at all, something with the magnet/electrical something?

I think I read that there are shims inside of it - can I removed them or something? As far as removing the clutch, it's just that one bolt in the center?

laramie_05MR

iTrader: (20)

It will not engage unless the engine is running.
You do have to smack it with some force to get it to move.
With the engine off have you tried turning the clutch face by hand? If you can turn it by hand with little resistance it is okay. If you can't turn it at all the compressor has locked up. There should be some resistance as there is pressure 3-4 bar in the system.
See post #8 for the shim set part number.

Yes it is held on by one 10mm bolt.

kyoo

iTrader: (29)

The clutch won't move at all if the engine's not on? The electric bit of it should still work, no?

When it's off, I can push it close to the compressor but it takes a good bit of force. There is absolutely zero resistance when I spin the clutch face. Does that mean no pressure in the system, or shims too far?