ecu signal to fan relay?

[Txakura]

Someone mentioned in one of the recent overheating threads that they had used a wire from the ecu to trip a relay for their own electric cooling fan. I just happen to have a reversible aftermarket fan from another car and would like to use it as my primary fan - to replace the mechanical.

 

Ea82, A/C so I have the secondary fan too.

 

Now, I would rather avoid a manual switch and don't go seriously off road (I'm not worried about immersing a running fan, if that happens I have much bigger issues) but the price of the universal thermostatic fan controllers is ridiculous.

 

It sounded like, if I connected to some signal from the ecu, it could activate a relay and be a fan controller.

 

Looking at the pinout from my ecu I'm not able to tell which lead that would be, I have the terminal numbers and the voltage listing, but not necessarily the function...

[GeneralDisorder]

Just wire the existing thermoswitch to control your relay ground and run both fans from the new relay. No ECU hacking required and I don't beleive there are any ECU outputs that would be useful.... in fact I don't think there are really any ECU outputs other than diagnostics on the EA82's.

 

GD

[Txakura]

Just wire the existing thermoswitch to control your relay ground and run both fans from the new relay. No ECU hacking required and I don't beleive there are any ECU outputs that would be useful.... in fact I don't think there are really any ECU outputs other than diagnostics on the EA82's.

 

GD

 

that sounds awesome, and very simple, I guess now I must test my thermoswitch to see if it is working correctly - Gloyale set me straight on how to check that -

 

30 amp relay okay?

 

thanks so much for clearing that up for me, I can do that with stuff I have on hand

[GeneralDisorder]

Yeah - I'm sure 30 amps would be more than sufficient.

 

GD