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S650 AC not working

phil314

Senior Member
Joined
Dec 28, 2014
Messages
356
Location
Otsego, Mn
Occupation
Instigator of Choas
Tried the AC in my S650 today and I'm getting nothing.
I flip the AC rocker switch and it lights up green, fan is on, temp set to cold.
Opening the rear door, I can see the belt turning the compressor pulley, but the compressor clutch is not engaging.
So I think it's an electrical problem, not a freon/leak problem.
I think the AC worked last summer, but not 100% sure.
There are probably some fuses/relay I should check, but no clue where they are on this machine??
Not yet anyway, I'll probably know soon enough, if someone can point me in a direction??
 

Zewnten

Senior Member
Joined
Apr 2, 2018
Messages
553
Location
Earth
Usually two reasons for this and the main one in my experience is lack of refrigerant in the system, any auto repair place should have an AC machine to hook up and check pressures. If that's all good then I would start looking at the electric side, starting with voltages at the compressor and work my way up stream. Do you have any codes?
 

Bls repair

Senior Member
Joined
Jan 21, 2017
Messages
1,612
Location
S E Pa
Occupation
Equipment operator,mechanic
Ac units usually have hi and low pressure switches for safety . If Freon is low it protects the pump from running and burning the pump up
 

phil314

Senior Member
Joined
Dec 28, 2014
Messages
356
Location
Otsego, Mn
Occupation
Instigator of Choas
Usually two reasons for this and the main one in my experience is lack of refrigerant in the system, any auto repair place should have an AC machine to hook up and check pressures. If that's all good then I would start looking at the electric side, starting with voltages at the compressor and work my way up stream. Do you have any codes?

No codes. Checking the pressures is probably a good idea anyway.
 

phil314

Senior Member
Joined
Dec 28, 2014
Messages
356
Location
Otsego, Mn
Occupation
Instigator of Choas
Ac units usually have hi and low pressure switches for safety . If Freon is low it protects the pump from running and burning the pump up

This makes sense. It's not turning on on purpose. I'll check the pressure.
 

Bswwood

Active Member
Joined
Jun 19, 2019
Messages
41
Location
Utah
The AC rocker switch is notorious for failing, even if it is lit green it may not be sending power to compressor. You can remove the small panel that holds the rocker switch and you will find a three-prong plug on the back, two white wires and one black, but a jumper wire between the two white wires and see if the compressor turns on. If it does not then it may be a problem with low pressure, but I would rule out the switch first. Also the machine will not code for AC issues because the AC is an independent system. There is a thermostat controller that has an LED that will flash codes that is found underneath the cab under the cover for the evaporator.
 

phil314

Senior Member
Joined
Dec 28, 2014
Messages
356
Location
Otsego, Mn
Occupation
Instigator of Choas
The AC rocker switch is notorious for failing, even if it is lit green it may not be sending power to compressor. You can remove the small panel that holds the rocker switch and you will find a three-prong plug on the back, two white wires and one black, but a jumper wire between the two white wires and see if the compressor turns on. If it does not then it may be a problem with low pressure, but I would rule out the switch first. Also the machine will not code for AC issues because the AC is an independent system. There is a thermostat controller that has an LED that will flash codes that is found underneath the cab under the cover for the evaporator.

Good to know. I'm picking up some gauges later today to check pressure. I'll also check the switch, but I never get that lucky. And I'll check the controller and look for the LED to see if it's flashing codes. I'll report back later when I've done some digging.
 
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