Hi I was using a derale standalone control that worked fine but wanted too try using the Ecu to trigger the fan I have 2 pins off the ecu for fan control I know one of the fan controls is used for when the ac is on should i use them both to trigger the one fan or just one output ? Thx Al

You will have to work out how they come on, depending on the model of subaru they differ widely. Foresters had a two speed fans in some models and the wrx ecu did some different things. I had the U1 (1996) ECU controlling the two speed fan in my first T3 conversion, the ECU turned on Fan 1 with the A/C (low speed) but as soon as the ECU saw a signal from the speed sensor it turned on Fan 2 (high speed). This was a bit of a pain having the fan roaring whenever the van was moving so I kept the ECU controlling Fan 1 but let the thermo switch in the radiator control high speed.

The factory manuals have the fan settings in them.

Hi thx for the reply got it all set up using a bosch relay wired up to fan 1 as noted in your reply. Let the motor get up to temp and fan relay was triggered by the ecu at 212 and fan ran for 2 or 3 minutes and dropped to 199 and shut off . I am using the torque app for all the data and a vdo water temp gauge and a infra red gun. I believe that the torque app reading from the ecu may be a little high as the infrared gun pointed at the temp sender reads 191 when app says 199. The ecu triggering the fan seems way better when cruising on the highway Thx for the advice