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Guys, I have some problem, after some investigations:

- usually when temperature passes half, radiator fan will on and once the temp is slightly below half, it stops
- problem is, sometimes even after half, the fan is still not moving causing the temperature raised high (almost red bar)
- i thought the fan broken, tried to knock the motor (suggestion from a friend), still not working
- but, when I turn the AC on, both fans (radiator & AC) are on now. Meaning, my radiator fan is working! It...