new t stat installed and fan not coming on
03-14-2024, 09:57 PM
#1
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Thread Starter
new t stat installed and fan not coming on
I installed a new t stat a little while ago, maybe 6 months ago. I left the engine running a while and the fan did not turn on. It used to work before this new t stat. The fan is OEM as well. Any ideas?
The reason for the lapse in time asking about the fan not running is that I have not driven this Jeep in a while, regularly. I mostly use it to pull my trailer in and out of the backyard, plus there's a large crack across the windshield that I have not replaced due to no comprehensive coverage. It's $275 to replace.
The reason for the lapse in time asking about the fan not running is that I have not driven this Jeep in a while, regularly. I mostly use it to pull my trailer in and out of the backyard, plus there's a large crack across the windshield that I have not replaced due to no comprehensive coverage. It's $275 to replace.
Last edited by xjallseasons; 03-14-2024 at 11:07 PM. Reason: didn't read post thoroughly.
03-14-2024, 10:59 PM
#2
What temps did you get up to?
I assume you're talking about the aux fan which I believe doesn't turn on until 226F or the ac/defrost is on.
I assume you're talking about the aux fan which I believe doesn't turn on until 226F or the ac/defrost is on.
03-16-2024, 07:32 AM
#4
CF Veteran
03-16-2024, 03:25 PM
#5
Senior Member
Thread Starter
I have a dummy gauge so no accurate numbers.
I pulled the temp sensor connector and it did not kick on.
But it does kick on when the a/c is on.
I pulled the temp sensor connector and it did not kick on.
But it does kick on when the a/c is on.
Last edited by xjallseasons; 03-16-2024 at 04:06 PM. Reason: didn't read post thoroughly.
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03-17-2024, 03:00 AM
#9
CF Veteran
Nvm, I just missed post #5 there
Ok so the fan works- the pcm "just doesn't turn it on". This has nothing to do with your thermostat, except:
It'll only come on when you run hot (see my post in other recent thread). It won't come on if you're not running hot , nor have no AC selected.
So, if we piece all things together: your new thermostat is working, you're not running hot, the pcm doesn't have to turn the aux fan on the fan works correctly when you select AC.
Ok so the fan works- the pcm "just doesn't turn it on". This has nothing to do with your thermostat, except:
It'll only come on when you run hot (see my post in other recent thread). It won't come on if you're not running hot , nor have no AC selected.
So, if we piece all things together: your new thermostat is working, you're not running hot, the pcm doesn't have to turn the aux fan on the fan works correctly when you select AC.
Last edited by Roler; 03-17-2024 at 05:34 AM.
03-17-2024, 03:24 AM
#10
CF Veteran
Which temp sensor connector did you pull...the one in the thermostat or the one near back of block
03-17-2024, 08:13 AM
#11
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03-19-2024, 11:20 AM
#12
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03-19-2024, 11:24 AM
#13
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So the other issue I have is that when I crank it over the check engine light comes on, that's new and the selector for vents won't turn off. I can't check to see if the aux fan kicks on when the a/c is on because I am not sure if it's the air just being on or the a/c. Also, I noticed that when the selector is in the heat mode that it really doesn't heat up even after keeping it on for several minutes.
03-19-2024, 05:18 PM
#14
CF Veteran
if you disconnected the connector on the thermostat, and the fan did not turn on...you have issues with your fan/wiring/fan relay or pcm
03-19-2024, 06:17 PM
#15
CF Veteran
So the other issue I have is that when I crank it over the check engine light comes on, that's new and the selector for vents won't turn off. I can't check to see if the aux fan kicks on when the a/c is on because I am not sure if it's the air just being on or the a/c. Also, I noticed that when the selector is in the heat mode that it really doesn't heat up even after keeping it on for several minutes.