john deere 644k A/C issues

[jeradcdn]

having issues with the a/c on this unit, the compressor cycles for about 3 seconds upon start up and thats it, changed out the high/low switch still nothing, thought maybe it was low on 134, it is not, power at the switch and high low switch. any ideas where i can go from here? thanks

 

[jeradcdn]

also gauges are reading high on the low side and low on the high side

 

[heymccall]

Gauge reading before starting, please.
And, since you say high is low and low is high, how can that be if the compressor only runs 3 seconds?

 

[jeradcdn]

80 on each before loader is running and the same when running as the compressor doesn't cycle!

 

[Birken Vogt]

Wire power direct to the compressor clutch so it is forced to stay on a little while and see what happens to the pressures and operation then, if there is not other electronics to get in the way. Condensor and evaporator fans running, of course.

 

[partsandservice]

At 80/80 the pressures are equalised. The pump is not turning. Either the clutch is not engaging or the pump shaft is broken.( Pump not turning when clutch engaged)

 

[jeradcdn]

ended up that the freeze control switch was at fault.