MegaSquirt PNP2 Outputs

So I've recently installed a MegaSquirt PNP2 in my '89 Fox and so far I love it. I love learning and tuning it myself. Already feels much better than it did with the A9L with a tuned SCT. I run dual Contour cooling fans which draw a lot of amperage on startup so I wired them into the MS separately. I wired them into output 1 and output 2 which are pins 24 and 25 on the options port. This supplies a ground signal when enabled.

My question is what can I use to turn my water pump on and off? I don't like my water pump running with key on engine off as it draws about 10amps so it's a battery killer if not planning on starting the engine. Also don't like the extra amp draw during cranking. I'd like to have my water pump come on after startup if possible. Has anyone done this? What wire can I use on the options port? Is it a ground or positive signal?

Under the Boost/Advanced tab and programmable on/off outputs I have FIDLE, Tach Out, Injector C, Injector D, Boost. Can I use one of those?

Thanks in advance for any help or guidance.

a91what said:

Fiddle is being used already for the idle valve.
Tach out is capable of pulling a relay in to power the water pump. Dont forget to place a flyback diode across the fan and water pump wiring to help increase the life span of both the relays and the motors. If you need part numbers I can supply that information.

I run a mark8 fan off one output (90amp initial draw) and dont have idle issues. I assume this is why you wired the fans separately?

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So I can use Tach out to turn my water pump on? Which pin number is that on the options port? Is that a positive or a negative signal? I'm not 100% sure what you mean by the diodes across the wiring.

Yes the reason I run them separately coming on at different temperatures is because both together draw well over 100 amps initially and obviously my idle drops. I haven't fully figured out all of the settings for a good solid idle as I'm still learning and tweaking.