Cooling fan not coming on
#1
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Driving home today I noticed my car getting a little warm when stopped. Came home, checked the fan and it wasn't coming on.
I hit the AC and that fan came on. I swapped the relays and the AC fan still worked, so both relays are good. I connected the fan directly to a battery and the fan comes on. I checked megasquirt and it's reading the correct water temps. I did swap the radiator a few weeks ago, but it's worked fine since then.
Any idea what's broke or how to fix it?
I hit the AC and that fan came on. I swapped the relays and the AC fan still worked, so both relays are good. I connected the fan directly to a battery and the fan comes on. I checked megasquirt and it's reading the correct water temps. I did swap the radiator a few weeks ago, but it's worked fine since then.
Any idea what's broke or how to fix it?
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The "maybe a random wire fell in half somewhere" theory was about all I've been able to come up with too ![Tear](https://www.miataturbo.net/images/smilies/tear.gif)
Thanks for the input. I was hoping there was something obvious I missed. Forgot to mention in the first post, fan fuse in the engine bay looks fine too.
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Thanks for the input. I was hoping there was something obvious I missed. Forgot to mention in the first post, fan fuse in the engine bay looks fine too.
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well it's possible the main fan is dead. ground TFA and GND in the diagnostics box to confirm the relay/fan is still working
I have a off-the-shelf MS3 that will turn the fan on, but it seems to be on a switched circuit. I'm wondering if I'd be better off to mod the MS or just simply run constant power to my fan relay.
this isn't hard.
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Per the first post, he swapped relays with the A/C fan, and the A/C fan still worked. He also applied battery power to the fan and it worked. So both the fans and the relay are ok - something is wrong either with the wiring (easy to diagnose in this case where the fan does not work, period) or with the MS fan relay circuit.
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