jorjio_k · Aug 30, 2010

<<<<<<<<<<<<<<<<<<<<updated >>>>>>>>>>>>>>>>>>>>>>
hello again;
i have discovered that the previous owner has installed a temperature sensor under the top hose and removed a plug from the pressure switches dunno which one but it has 2 yellow thin wires and they r bridged together.it seems when the temp gauge gets to one mark above center,the condenser fans run in parallel (fast),although they r running in serial when ac is on.this overheating issue applies only when ac is on and at idle,when temperatures get over 35 celsius.my diagnostic makes me think that the aux fans rn't running at parallel when they must untill it is to late and the freon is very hot thus heating the engine,and when engine is overheated (temp above middleat one mark),they will run in parallel when this thermo sensor gives them the order.i have noticed that the cold air coming from ac is getting warmer unless i accelerate thus cooling the freon in condenser,and air will be colder.
now the question is,should i keep this thermo sensor under the top rad hose and keep the system as it is,or i must get it back to normal.my doubts are that one of the pressure switches for the ac is duffed,i don't know if that was the reason for installing a thermo sensor instead of replacing the swithes,was it a cheaper escape route 6 years ago?
any suggestions?

wammers · Aug 30, 2010

jorjio_k said:
<<<<<<<<<<<<<<<<<<<<updated >>>>>>>>>>>>>>>>>>>>>>
hello again;
i have discovered that the previous owner has installed a temperature sensor under the top hose and removed a plug from the pressure switches dunno which one but it has 2 yellow thin wires and they r bridged together.it seems when the temp gauge gets to one mark above center,the condenser fans run in parallel (fast),although they r running in serial when ac is on.this overheating issue applies only when ac is on and at idle,when temperatures get over 35 celsius.my diagnostic makes me think that the aux fans rn't running at parallel when they must untill it is to late and the freon is very hot thus heating the engine,and when engine is overheated (temp above middleat one mark),they will run in parallel when this thermo sensor gives them the order.i have noticed that the cold air coming from ac is getting warmer unless i accelerate thus cooling the freon in condenser,and air will be colder.
now the question is,should i keep this thermo sensor under the top rad hose and keep the system as it is,or i must get it back to normal.my doubts are that one of the pressure switches for the ac is duffed,i don't know if that was the reason for installing a thermo sensor instead of replacing the swithes,was it a cheaper escape route 6 years ago?
any suggestions?

Return all the wiring to standard and work from there. It sounds as though the condensor fans are being controlled by engine temp and not by refridgerant temp. The condensor fans should come on at low speed only, at a certain engine temp, to assist engine cooling (with aircon switched on) this is because of the extra load imposed on the engine by driving the aircon compressor. They should not come on at all with aircon off as i understand it.

jorjio_k · Aug 30, 2010

wammers said:
Return all the wiring to standard and work from there. It sounds as though the condensor fans are being controlled by engine temp and not by refridgerant temp. The condensor fans should come on at low speed only, at a certain engine temp, to assist engine cooling (with aircon switched on) this is because of the extra load imposed on the engine by driving the aircon compressor. They should not come on at all with aircon off as i understand it.

they r on at low speed only when ac is on in my truck.the only time they get fast is when temp gauge is one mark above middle (controled by engine temp)by the thermo sensor installed,and when ac is on.anyway temp gauge is at middle always and during all temp except when ac is on

wammers · Aug 30, 2010

jorjio_k said:
they r on at low speed only when ac is on in my truck.the only time they get fast is when temp gauge is one mark above middle (controled by engine temp)by the thermo sensor installed,and when ac is on.anyway temp gauge is at middle always and during all temp except when ac is on

If it's running ok and not overheating leave it alone then. You can't have it both ways. The fans are supposed to come on at slow speed to assist engine fan when engine gets hot by driving aircon pump. They are not supposed to come on at high speed unless signalled to do so by aircon temp and pressure switches to cool condensor. It appears to me that someone has taken the aircon switch out of the equation and rigged the fans to be controlled by engine temp. There are plenty of instances of these fans being used instead of the viscous unit by wiring in a couple of relays and a thermostat, mostly on the diesel models. I have this setup on my DSE. Were the fans will come on to assit cooling of engine even if the aircon is switched off. And work normally to cool condensor when aircon is on. That is the way it should be done. From what you say I don't think yours has been done correctly and that's what's giving you your problems. But maybe the temp gauge going up and down like a brides nighty is acceptable living where you live in the temperatures you get out there, if that method is doing a job for you. Other that that, as i say return wiring to standard and start again.

jorjio_k

Active Member

wammers

No longer with us, RIP

jorjio_k

Active Member

wammers

No longer with us, RIP

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