Question about 1999 GMC Suburban

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My A/C Condenser Fan runs very slow. Where should I start looking for the problem?

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  • yadayada
    yadayada May 11, 2010

    are you sure it isn't a variable speed fan based on the high side pressure?



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Check voltage at fan if above 12v replace fan Warning must be checked with vehicle running and A/C on

Posted on Jun 29, 2009


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Ac condenser fan starts running as i start engine

If the control panel is in a/c or defrost mode then this is a normal condition. If the control panel is off then the condenser fan relay may be bad and the contacts are stuck on.

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Why my A/C condenser fan won t stop running, dodge ram 2008

To clarify, the compressor and fan will run in defrost mode. The compressor and fan runs to dry out the air blowing onto the windshield.
Now if the condenser fan runs in "heat" you may have a problem with the fan relay or the main controller.

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Condenser fan not engaging when A/C turned on. All fuses and relays look fine. Tested fan with eternal power and it runs.

Possibly low on refrigerant. When system is low on freon, it does not build up enough high side pressure to engage the condenser fan . When pressure is high enough. a high side pressure switch kicks on the cond. fan to maintain high side pressure. Have the system evacuated and recharged to proper level. A system dye can be added to check for any possible leaks.

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2008 ford expedition air conditioning problems

the ac pressure depends on the gas in use
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overheating at slow speeds indicate an inefficient coolant fan and the high ac pressures indicate that the condenser fan also is not operational
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Air conditioning not working on BMW 325 XI

with a/c on, with condenser fan must be running to remove heat from condenser, check and make sure fan is running

Jul 15, 2012 | 2004 BMW 3 Series

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Car Condenser Fan

No the fan only comes on when the AC system high side pressure reaches a predetermined point, so it may not run for some time after the compressor engages.

Feb 09, 2012 | Honda Cars & Trucks

1 Answer

I have a 2002 Dodge Ram Quad Cab 4x4. The a/c runs great as long as the truck is moving, but as soon as you come to a stop it starts blowing warm air. Please help.

Generally if the a/c works fine at highway speeds but kicks out or slowly begins to blow warmer and warmer air as the vehicle is driven at slow speeds or is stopped the a/c condensor cooling fan is usually at fault. At highway speeds there is enough air being forced through the radiator, condenser, and oil coolers to keep everything working and cool but when the vehicle is moving slowly or is parked the electric and mechanical cooling fans have to be working to pull enough air through to keep things working. If the cooling fan isn't working or can't pull enough air through the a/c condensor the system will kick out once the internal pressure reaches a certain point. Once the vehicle is moving again the system can get rid of the heat that it has gathered from the passenger cabin, the pressure drops back to normal and the system cools again. I would start by looking for a blown cooling fan fuse in the fuse panel under the hood. Usually they are 25 amps or larger and run only the cooling fan.

Jun 14, 2010 | 2004 Dodge Ram 1500

1 Answer

The cooling fan on the driver side of the radiator does not work i just put a new one where the water hose side is and now it runs but the other one does not. I put one new thermostat and one new fan...

One of the fans is for your radiator and the other is your condenser fan (for your air conditioning). The condenser fan starts at a higher temp than your radiator fan.
To test the condenser fan (the one on the right side, facing the car) unplug the electrical connector at the motor and use jumper wires to connect the fan directly to the battery. If it runs, check the fuses (engine compartment far upper left as you face the car), then the relay (right front corner of the engine compartment as you face it). The radiator fan typically engages between 189 and 199 degrees, but the condenser fan typically engages between 217 and 232 degrees. In other words they don't necessarily run at the same time. First of all, try letting the car run until the engine is warm WITH the ac running. If the condenser far does not run, then go through the checking procedure.
I hope this gets you started on a fix.

Oct 22, 2009 | 1995 Honda Accord

2 Answers

After repairing the fan on the cooling system our 2002 Nissan Xterra air conditioner blows warm air until hitting the highway and then it will cool off. There was no problem with the air until the repair

Need to make sure the fan is acually running with ac on.If so see if the fan is pulling air,or pushing air.Is the fan on the out side of condenser or inside?The fan ,if on the inside of condenser(engine side)it should pull air.If it is on the out side of the condenser it should push air.If all this checks out,then see if the fan is running slow,it should run very fast.Is there another fan?Is it working?It to should be running with ac on.

Aug 06, 2009 | Nissan Xterra Cars & Trucks

2 Answers


jtaddiken: A/C systems rely on air flow over the condensers and is the component that looks like a radiator. This component is also located in front of the radiator while the fan is behind the radiator. Consequently if it does not function, especially on hot days the pressures in the condenser will build. The condenser is where the freon is condensed from a gas to a liquid. The byproduct is HEAT!
SO, You could have a number of problems occurring. 1. Fuses: in the main fusible link box are located on the left side of the engine compartment. It's a large black box about a foot long and 4 inches wide.When you remove the cover, you will see some fuses with clear plastic tops on them. They will have numbers on them.
The top fuse will have 140 the next two spaces down should be empty. Then there should be a 30, 30, 30, 50, 40, 40, 30.
You want to check the 30 which is the first one in the line as you go down from the 140. Look through the clear plastic top and compare it to the other ones. if the center of it is burned or missing, it is no good.
Pull it out and get a replacement with the same number.
IF it blows again, you have an electrical short which you can either chase down or bring to a professional.
2. Relays: There should be another box or an arrangement with 4 relays. Three will run side by side and one will be at the other end of the box. Based on the schematic I am looking at, they all work in conjunction with each other. The only variable is the condenser fan. But the radiator fan is designed to run whether the A/C is turned on or not. A failure of any one of these will render the condenser fan inoperative.
3. The fan motor has failed. You can do a simple test which you might do before you do check #2. That is, unplug the fan motor and supply it with an external power supply. Both the positive and negative. The negative is supplied through the relay and the other side to the fan is hot all the time.If the motor runs then continue with the other tests, if it doesn't , the motor is bad.
4. The pressure switch. If the pressure switch has failed, it will create an open circuit to the relay that also kills the compressor clutch so the A/C stops cooling. It can be located on the receiver drier or on the high pressure line close to the drier.
One which malfunctions can also keep the Condenser fan from running.
5. An A/C condenser with a lot of debris built up on it. There is significantly more air being forced through the condenser coils than the fan can pull through the radiator, air leaks between the radiator and condenser, thus minimizing the suction through the condenser.
I hope I haven't created a confusing situation rather than a plausible solution. I try to not only solve the problems, but give a basic understanding of how it works and then why it may not work.
Sometimes people will grade me on my assistance. Most of the assistance I have given, has not yielded a "well he helped" OR BOY, this guy should be giving advise in loading rocks!"
Any way, if I have helped and you need further assistance, I would be delighted to assist. Good Luck.

May 06, 2009 | 2002 Toyota Highlander

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