cooling fans not working

1999 MITSUBISHI PAJERO
143,000 MILES • 1.8L • 4 CYL • 4WD • AUTOMATIC
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THO-MOH
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However, when i disconnect the temperature sensor, fans turn the engine sign is displayed. i checked the temperature sensor as the temperature of the coolant increases the resistance decreases, also check a relay switch, and fans they are fine. so what could be the problem? please help
Sep 8, 2019 at 10:46 AM
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JACOBANDNICKOLAS
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Welcome to 2CarPros.

I have to tell you that this car isn't offered in the US, so my technical information is extremely limited. However, you did the test where checking resistance based on temp. However, do you have a chart indicating what the resistance should be based on temp? It may be reacting, but not reacting correctly.

https://www.2carpros.com/articles/symptoms-of-a-bad-coolant-temperature-sensor

Let me know.
Joe
Sep 9, 2019 at 6:16 PM
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FLWESANYA
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1999 Mitsubish Pajero IO GDI(H76W-0032372: My car is overheating. I changed the thermostat. But it still overheats. It ruptured the radiator cover and I had to replace with a new radiator after failing to get the spare part separate. After putting the new radiator I noticed that the fan takes long to come on. And when the fan comes on it runs at a very slow speed for a few seconds and stops before the coolant cools. Now Is it the fan mortor that is failing or what is causing this? If I remove the thermostat from the socket the fan runs at normal speed but the car idling does not stabilise and the engine light in the dash board goes on. Kindly assist me with an answer.
Jul 27, 2020 at 12:07 PM (Merged)
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RASMATAZ
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Scan the computer for codes/s-start here -let us know-could be the coolant temperature sensor acting up-
Jul 27, 2020 at 12:07 PM (Merged)
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FLWESANYA
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I have done the scan: 'Fun control unit needs replacement'. That is all I was told.
Jul 27, 2020 at 12:07 PM (Merged)
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WRENCHTECH
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I don't have specific specs on that car but most all of these fans are intentionally designed to come on at higher temps for emissions reasons. Most don't come on until225 of higher and that is normal. As long as the fan is shutting back off, i doubt it has a problem at all.
Jul 27, 2020 at 12:07 PM (Merged)
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FLWESANYA
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Thanks. Now I am getting confused. What controls the speed of the fun? Because I see that when the fun is eventually started it moves at a very slow speed for a few seconds and then it stops. This causes engine overheating.
Jul 27, 2020 at 12:07 PM (Merged)
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SALIZ
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The radiator fan is not working. The fuse is fine
Jul 27, 2020 at 12:07 PM (Merged)
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WRENCHTECH
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As I stated, I don't have a wiring diagram for that car but many have 2 speed systems. It could also be a bad fan motor but you could determine if that's the case by observing how it works with the A/C
Jul 27, 2020 at 12:07 PM (Merged)
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JACOBANDNICKOLAS
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Run power directly to the fan motor to make sure it is good. If it is, check the fan relay. Switch it with another relay that has the same part number. If that still doesn't work, check the coolant temp sensor.
Jul 27, 2020 at 12:07 PM (Merged)
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FLWESANYA
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Ok let me tray and observe. I will come back to you later.
Jul 27, 2020 at 12:07 PM (Merged)
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KHLOW2008
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No code reader or scan tool would tell you what component needs to be replaced. They only tell you that a certain circuit has a fault.

What is the EXACT trouble code that you are getting?
Jul 27, 2020 at 12:07 PM (Merged)