Radiator Fan not working

Tiny
CPO688
  • 2002 CHEVROLET CAVALIER

Engine Cooling problem 4 cyl Two Wheel Drive Manual 180000 miles

Radiator fan only runs when a/c is on. I replaced temp sensor located on top pipe on right front of engine. Still problem is the same. Also if I unplug the sensor the fan runs continuously.

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Friday, September 24th, 2010 AT 3:10 PM

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Tiny
WRENCHTECH
  • EXPERT
  • 20,829 POSTS

Changes are the system is working just fine but the gauge is off a little. I would run this test, use an infrared temp gun or a thermometer and just the temperature of the engine while it is running and compare it to the gauge.

Here is a guide to help you.

https://www.2carpros.com/articles/how-to-use-an-infrared-temperature-meter

Please let us know what you find.

Cheers

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Friday, September 24th, 2010 AT 3:15 PM
Tiny
CPO688
  • MEMBER

I check the engine with the turkey thermometer and you are right it is running cooler than the gauge says about 12 degrees. So what should I do change the gauge out?

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Friday, September 24th, 2010 AT 5:58 PM
Tiny
WRENCHTECH
  • EXPERT
  • 20,829 POSTS

What happens is the gauge becomes a little off over time and vibration pf the car which means you need the gauge which may or may not be available separately.

Here is some more info I found

Cooling System Description and Operation

Cooling Fan Control

The engine cooling fan system consists of one cooling fan and one relay. The relay is powered by the battery positive voltage circuit and controlled by a switched ground from the powertrain control module (PCM).
During operation, the PCM supplies the ground path for the cooling fan relay through the cooling fan relay control circuit. This energizes the cooling fan relay coil, closes the relay contacts, and supplies battery positive voltage from the cooling fan fuse through the cooling fan motor supply voltage circuit to the cooling fan. The cooling fan motor is grounded through its own ground circuit.
The PCM commands the fan on under the following conditions:

* Engine coolant temperature exceeds approximately 106 C (223 F).
* A/C refrigerant pressure exceeds 1310 kPa (190 psi).
* A/C is requested and vehicle speed is below 100 km/h (62 MPH) with A/C pressure above 1413 kPa (205 PSI).
* Vehicle speed is less than 8 km/h (5 mph) for more than 750 seconds. The fan will turn off when vehicle speed is greater than 8 km/h (5 mph) for more than 20 seconds.

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Friday, September 24th, 2010 AT 6:03 PM
Tiny
CPO688
  • MEMBER

Okay thanks for the information. Should I just put a piece of tape over by the needle as normal operation temperature?

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Friday, September 24th, 2010 AT 6:11 PM
Tiny
WRENCHTECH
  • EXPERT
  • 20,829 POSTS

That will work just fine, Here is a guide to help you know if you have a problem or not

https://www.2carpros.com/articles/symptoms-of-an-overheating-engine

Please use 2CarPros anytime, we are here to help. Please tell a friend.

Cheers

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Friday, September 24th, 2010 AT 6:19 PM
Tiny
CPO688
  • MEMBER

Thanks I will, this site is great!

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Friday, September 24th, 2010 AT 6:49 PM
Tiny
2CARPROS MIKE
  • ADMIN
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We have a lot of professional technicians that are both paid and volunteer a considerable amount of time trying to help.

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Thursday, September 30th, 2010 AT 11:20 PM
Tiny
MLEWIS71
  • 2002 CHEVROLET CAVALIER

I have 2002 Chevy Cavalier 2.2L with approximate 80,000 miles. Last week while sitting at idle in the parking, I heard a faint pop and the AC started blowing hot air. I also noticed that the engine temp had risen slightly above the normal temperature.

When I checked under the hood, I noticed two things:

1)The radiator fan was not turning
2) The AC also began to cycle on and off erractically. I could also hear the RPM's surging up and down each time it cycled.

The next day I started the car and the radiator fan seem to be working. The AC also worked properly until the engine reached normal temperature at which point the radiator fan stopped working again. The AC cycling and RPM surges also returned.

While driving, the car seems to run fine. However, the car temperature rises and the AC blows hot air when idle or in traffic.

My problem is very similar to the one identified in the following post: http://www.chevroletforum.com/m_3913/printable.htm

One last detail: I have not seen the radiator fan moving the last few times I started the vehicle (even when cold) I also turned the fan manually. It is unobstructed and turns easily.

I have already replaced both the coolant temperature sensor and coolant sensor connector. However, the problem remains the same as before. Could it be the fan motor or fan relay? If so, I have a few questions.

1) Is there an easy way to check the fan without removing the connector? Especially since can't see how to remove it. I am also not sure that I can reach it either because the connector seems to be underneath the fan and recessed into the shroud assembly.
2) Where should I look for the fan relay?
3) Or am I completely off base?

Thanks in advance
Michael

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Tuesday, October 3rd, 2017 AT 9:46 PM (Merged)
Tiny
E40WATER12
  • MEMBER

Yes sounds to me you got some kind of problem there. Have you got a chagring system load tested.
You could have a bad fan relay switch, So you have mentioned youre rad fan works right. Now if you have replaced coolant sensor and temp sensor, I would recommend doing the easy trouble shootong first. I would do what I have listed above then. Work onto the other things later.

Good Luck.

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Tuesday, October 3rd, 2017 AT 9:46 PM (Merged)
Tiny
MLEWIS71
  • MEMBER

Unfortunately, I am still having the same problem. You mentioned having the charging system load tested. Is it necessary for me to go to an A/C service provider to have this test performed?

Michael

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Tuesday, October 3rd, 2017 AT 9:46 PM (Merged)
Tiny
EAGLES
  • 2002 CHEVROLET CAVALIER
  • 13,000 MILES

I have a 2002 cavalier I put a new thermostat in and the engine runs hot enough for the engine fan to come on put it is not making the engine cool enough to shut the fan off. If I take the thermostat out the engine does not run hot at all and there is new fluid in there too could there be something blocking the flow of water to the thermostat when I put it back in. Can someone tell me where the oil filter is on the engine of my other car a 2011 Impala

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Tuesday, October 3rd, 2017 AT 9:46 PM (Merged)
Tiny
HMAC300
  • EXPERT
  • 49,800 POSTS

Theoil filter of your impala is on the front of car by bottom you shold be able to see it by the drain pan look straight up. As far as your cavy have the coolant system pressure checked as it may be ahead gaslket problem. Of cours i'm assuming you have tried a new thermostat. Also check radiator with fans disconnected for cold spots if you feel any the rad is bad.

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Tuesday, October 3rd, 2017 AT 9:46 PM (Merged)
Tiny
HMAC300
  • EXPERT
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There is only one pic attached. It may be your ect not reading right there may also be nothing wrong at all with it as well.

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Tuesday, October 3rd, 2017 AT 9:46 PM (Merged)
Tiny
DALEADAMSON
  • 2000 CHEVROLET CAVALIER

Engine Cooling problem
2000 Chevy Cavalier 4 cyl Front Wheel Drive Automatic 145, 00 miles

my cooling fan does not come on until 225 degrees and does not run when engine is turned off. I have replaced the thermostat, inline sensor, and the relay switch

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Tuesday, October 3rd, 2017 AT 9:46 PM (Merged)
Tiny
MMPRINCE4000
  • EXPERT
  • 8,695 POSTS

Use a scan tool to see what temp. The PCM is reading. Your gauge could be off or sender is bad.

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Tuesday, October 3rd, 2017 AT 9:46 PM (Merged)
Tiny
ALXOLI
  • 2001 CHEVROLET CAVALIER

Engine Cooling problem
2001 Chevy Cavalier 4 cyl Front Wheel Drive Manual 135000 miles

While sitting in traffic for long periods of time, my veh will start overheating. I can turn my ac on and the fan will kick on and cool the engine but otherwise the fan will not come on. I had someone check the relays and fuses and they appear to be working. I have not replaced them to see if that corrects the issue.

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Tuesday, October 3rd, 2017 AT 9:46 PM (Merged)
Tiny
JDL
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Hello, anybody check the coolant temp sensor? Are there any codes? Some of the national brand autostores will check codes for free.

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Tuesday, October 3rd, 2017 AT 9:46 PM (Merged)
Tiny
ALXOLI
  • MEMBER

I replaced the coolant temp sensor along with the fan relay and the fan is still not coming on. Any other ideas?

Michelle

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Tuesday, October 3rd, 2017 AT 9:46 PM (Merged)
Tiny
JDL
  • EXPERT
  • 16,353 POSTS

Hi, I should have told you to check wiring circuits before replacing anything. If you unplug the CTS and turn on the key, does the fan come on? With key on, can you check for voltage at one of the plug terminals?

Were there any codes?

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Tuesday, October 3rd, 2017 AT 9:46 PM (Merged)
Tiny
ALXOLI
  • MEMBER

The car is not throwing any codes. I went ahead and just repl those parts since they were not expensive just to see if it would take care of the issue.
I did check the wiring and everything appeared fine. The only issue I had was the temp sensor was pretty corroded and since it was only about $15, it was just easier to repl.

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Tuesday, October 3rd, 2017 AT 9:46 PM (Merged)

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