Auxillary ect sensor/efan circuit

[johnmaster]

Wondering if I can install an auxillary temperature sensor and use the pcm to control a 12v output (like a fan relay). Anything come to mind? For instance a temp sender mounted on an intercooler triggering a fan relay if a certain temp is satisfied.

[Mr. P.]

You don't need the PCM's involvement to do that; just get a "temperature switch" and wire it to trigger a relay, there are tons on fleabay for $25-50.

Mr. P.

[Mr. P.]

Is this for an air-to-water heat exchanger, when the vehicle is stopped and there's no airflow to cool it so you activate a dedicated fan??

[johnmaster]

You don't need the PCM's involvement to do that; just get a "temperature switch" and wire it to trigger a relay, there are tons on fleabay for $25-50.

Mr. P.

That makes much more sense...sometimes I try to get complicated when a simple approach is always the best. I am looking and finding a good handful of simple options for cheap, thank you again!

John