Chryco Psycho

06 Ram , the A/C will work on & off but now is working for 30 seconds or so , it then returns to warm air , it seems all the sensors are inside the heater box . I hav no clue what to look for or change to make it work again , I spent 3 hrs tonight trying to remove the dash cover & after removing 300 screws the cover would still not move , I assume the whole frame needs to be removed ?
this is the only vehicle in 75+ that I have owned that ever had working ac , I do not care but I need iot for customers
Any help would be appreciated

madhat

What are your high and low pressures?

Is the condenser freezing up?

Is the wiring harness on the back of the compressor intact? They have had chafing issues.

Could be a high pressure switch.

Chryco Psycho

I checked the wiring at the compressor , it seems Ok but I will check again .
I did not pay enough attention to the numbers but the the guage at the front by the condenser was almost pegged & would fluctuate down the 60% , the guage at the rear was 40% [low pressure I believe] the condenser in front of the intercooler was warm . Where is the high pressure switch located & can it be accessed without removing the dash ? I know nothing about AC , I lived my whole life in a climate where is just was never needed LOL all we needed was a heater even on summer nights

SolarExpress

Mine was working/not working. Turns out I had two issues. 1.) The A/C line running to the condenser had a little rubbed through it from the radiator fan shroud. That probably saved my compressor because 2.) the fan clutch had died. The hose was about $150 IIRC and the stinkin' clutch was $400! $985 dollars later all works well. I had been having issues for some time, most of the year in fact. Had it recharged and it seemed to fix it. Apparently the fan clutch was dying coupled with the worn through hose finally killed it enough to have a serious look at it. I have cold air coming from both driver and passenger sides.

PWong

Sounds like low refrigerant to me. The Hi and Low pressure switches are on the refrigerant lines/compressor under the hood. If you jump the Low pressure switch and the compressor runs contiuously then your refrigerant is low.

Chryco Psycho

well I took it in & had the system checked , they refilled the 134a but it still will not engage all the time , of course it worked fine while at the a/c shop

1-2-3

might be the blend door slamming shut, throwing it over to heat.

Chryco Psycho

no it will blow cold for 30 seconds & then goes back to outside air temp
the blend door seems to be working fine , it changes air temp properly

Spooler

Sounds like the compressor clutch unless the high or lower pressure switch is being tripped.

Chryco Psycho

I am thinking it has to be a faulty pressure switch as the clutch has always engaged
thanks for the insight , this is the only vehicle I have ever owned with a/c

1-2-3

Wow. You must not be from Texas. We use AC even during the winter.

Chryco Psycho

I lived most of my life in western Canada where night temps in the summer time drop into the 40-50 F range so we use the heater year round , the few "warm" days we get were easily tolerated with no A/C!! We averaged 5 days / year where ti got over 85* f

Chryco Psycho

well so far no clue , took it a shop to service it & they overpressured it so now it needs a new high pressure valve , new expansion valve , new compressor , new accumulator & new clutch , $800 & counting & no clue if we have solved the intermittent problem yet !!

vcoyle

Chryco, did you ever get this resolved? I had the same issue and had to get an AC control head replaced??? not exactly sure what that is, but it was to the tune of $400. Hopefully the issue will now be resolved.

Busboy

First if the Hi side is almost pegged you have a blockage in the system and the reason it cuts off is it is tripping the High pressure cut off switch. I don't think even with an inoperative clutch fan that you would get the high pressure up that high. Because the pressure does climb I think the compressor may still be ok but you may have had the accumulator burst internally or could just be dirt. Either way you need an expansion tube and an accumulator and a flush, evacuate and recharge. HP sw is down by the compressor on the output side.