Toysrme - how do you wire the capacitor for soft start - parallel across the two wires to take the load? And what size would you need - fairly hefty I imagine?cribbj build a pwm controller for your fan so that the speed can be adjusted. You can also make a soft start using a capacitor.
Electric motors require 3-4x the rated constant power useage when they are stalled.
the linked ones look ok also.
My ecu has 8 outputs (including 4pwm) and they are all earths (current sink to use youtr words?) with maximum current of 1 amp each - sufficient to drive a relay (mechanical or electronic) so this should be ok. I've had a lookat those ssr's, they have a lovely low operating current.Edz, can't answer the question you posed to Toys, but I had the same problem, not only with the fans, but with the fuel pump. I can get a logic level PWM output out of the ECU, but it's too weak to power anything.
A great way to "amplify" this signal is to use a 20 to 50 amp solid state relay, (SSR) like those from Magnecraft Crouzet, or your best local supplier. These SSR's switch so fast, they're more than suitable for the application.
Trigger the SSR with the logic level signal out of the EMS, then power the fans or fuel pump from the SSR.
Just be sure to pay attention to the wiring diagram for the SSR when you buy it, as your EMS output may be either current source, or current sink, and you have to buy the compatible SSR for that.
I've had this setup working well for the fuel pump in my Supra for the last 3-4 years.