Cooling Fan Thermo Switch Location ?

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Posts: 9
Joined: Mon Dec 30, 2019 5:28 am
Car: 1994 Nissan 240sx RB 25 DET swap

Cooling Fan Thermo Switch Location ?

Postby [email protected] » Tue Dec 31, 2019 6:34 am

I have a 240 SX with an RB 25DET swap. Where is the cooling fan thermal switch located?
My fan will not come on when engine warms up thank you.


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NukeKS14
Posts: 46
Joined: Wed Apr 10, 2019 2:50 pm
Car: 1995 240SX SE - KA24DE-T
2014 Camaro SS 1LE

Re: Cooling Fan Thermo Switch Location ?

Postby NukeKS14 » Tue Dec 31, 2019 10:41 am

Is it an aftermarket fan? The OEM S14 fan is controlled by the ECU. What 240sx chassis, S13 or 14?

If S14, there is a fuse and a pair of relays to check.

First is a 7.5A fuse on drivers side floorboard. Its labeled AC I believe. Neither slow or high speed fan will come on with that fuse blown or missing.

There are 2 relays in fusebox under the hood for high and low fan speed.

Short answer. Its controlled by ecu. Long answer depends on your chassis and ecu ,(stock, aftermarket) on where to start troubleshooting.

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Posts: 9
Joined: Mon Dec 30, 2019 5:28 am
Car: 1994 Nissan 240sx RB 25 DET swap

Re: Cooling Fan Thermo Switch Location ?

Postby [email protected] » Tue Dec 31, 2019 11:25 am

Great! Thanks for your reply… The car is a S 14 Zenki ?
1995. So you're saying if that's the case the fan is controlled by the EC you? Therefore I should check relays and a fuse ?

[email protected]
Posts: 9
Joined: Mon Dec 30, 2019 5:28 am
Car: 1994 Nissan 240sx RB 25 DET swap

Re: Cooling Fan Thermo Switch Location ?

Postby [email protected] » Tue Dec 31, 2019 11:27 am

Great! Thanks for your reply… The car is a S 14 Zenki ?
1995. So you're saying if that's the case the fan is controlled by the EC you? Therefore I should check relays and a fuse ?


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