Radiator fans

Joeglia

New member
Joined
Jun 29, 2016
Messages
17
Reaction score
0
Points
0
1998 Montana. I notice the driver side fan is running but the passenger side is not running. Should both fans be running when the AC is on or does one run and the other kicks in at a certain point related to the temperature sensor? I have a feeling BOTH should be running simultaneously. Any help greatly appreciated. I plan on seeing if I can take the driver side wires over to the passenger side to see if it actually works and back track from there. Thanks
 
Last edited:
have you switched the fan relays to check if you have a bad relay?
 
I swapped COOL FAN 1 and COOL FAN 2 relay and no difference. Passenger side never comes on. There is one more relay just called COOL FAN, it is a 5 pronged relay that I am going to try and determine how to test. I also placed a volt meter on the fan wire itself and have no voltage but again, I am not sure if the voltage is sent AFTER possibly the temperature sensor kicks in and sends voltage. I did not want to run the vehicle too long without knowing if the fan should be running. I could have my daughter run with the AC on all the time so at least one fan is running and cooling the radiator. I did not test the fan direct yet to battery but may do so but I want to try to determine how the voltage is sent. There are also 2 30AMP fuses and those appear to be good as well.
______________________________
 
from everything I see both fans should be running, unplug the temperature sensor and it goes into fail safe mode, both fans should come on.
 
I solved this issue and caused this issue. Neighbor down the street has a 98 Chevy Venture. She allowed me to start it and watch the fans and confirmed for me that both fans should be running. After testing all 3 relays and determining they were good with an ohm meter and volt meter, I waited until fans stopped running then tried to spin them by hand. I noticed the one that was working spun easily but the other was "stuck". After pushing harder it spun so I looked between the radiator and fan and could see a plastic HAYDEN e-cooler clip causing just enough friction for the fan not to spin. I pulled the clip tighter, towards the radiator so the fan would not hit and bingo all is good. FAN SPINS NOW. I used these clips to hold the external transmission cooler in place, so this is my fault, I must not have pulled them tight enough from the start and went look for a more difficult solution to a simple fix. Thank you to those on the board who helped.
 
great easy fix!
 
So when should the fans be running and how loud are they? I don't know if I have ever heard mine kick on? I mean, I know I have let it idle and have seen the temp needle rise, but unless they are super quiet, I really don't think I have heard them come on.
______________________________
 
you probably wont hear them from inside, you have to open the hood
 
Back
Top