# Need help with function logic for aux coolant pump control

**URL:** <https://community.ecumaster.com/t/need-help-with-function-logic-for-aux-coolant-pump-control/5410>\
**Category:** V3 SOFTWARE\
**Created:** [March 22, 2026, 7:30pm UTC](https://community.ecumaster.com/t/need-help-with-function-logic-for-aux-coolant-pump-control/5410 "2026-03-22T19:30:32Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![kalns](https://avatars.discourse-cdn.com/v4/letter/k/74df32/32.png) [@kalns](https://community.ecumaster.com/u/kalns)\
**Post date:** [March 22, 2026, 7:30pm UTC](https://community.ecumaster.com/t/need-help-with-function-logic-for-aux-coolant-pump-control/5410/1 "2026-03-22T19:30:32Z")

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Hello.

I have a need to control auxilary coolant pump, the issue is that its controled with relay and not PWM, no option to add pwm drive for it at the moment.

My idea is that it should only be on if CLT \>= 60\*

and maybe if CLT \<20 off, if CLT \>20 \< 60 turn on for 5 seconds and off for 5 maybe.

I cant realy figure out for the function logic could be created in cunction menu. Should I use multiple functions with diffrent statements and cycle it like so or there is some bether way to do this ?

Thanks.

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**Author:** ![Jadzwin\_ECUMASTER](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/jadzwin_ecumaster/32/28_2.png) [@Jadzwin\_ECUMASTER](https://community.ecumaster.com/u/Jadzwin_ECUMASTER)\
**Post date:** [March 23, 2026, 11:13pm UTC](https://community.ecumaster.com/t/need-help-with-function-logic-for-aux-coolant-pump-control/5410/2 "2026-03-23T23:13:32Z")

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Use electric water pump strategy and enter DC 100% in all parameters fields

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<div class="post-metadata">

**Author:** ![kalns](https://avatars.discourse-cdn.com/v4/letter/k/74df32/32.png) [@kalns](https://community.ecumaster.com/u/kalns)\
**Post date:** [March 26, 2026, 11:28am UTC](https://community.ecumaster.com/t/need-help-with-function-logic-for-aux-coolant-pump-control/5410/3 "2026-03-26T11:28:36Z")

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And output I should assign under Functions am i geting this right ? Because I dont see any other way in menu how to assign this.. Or am i missing something ?

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<div class="post-metadata">

**Author:** ![Jadzwin\_ECUMASTER](https://dub1.discourse-cdn.com/flex013/user_avatar/community.ecumaster.com/jadzwin_ecumaster/32/28_2.png) [@Jadzwin\_ECUMASTER](https://community.ecumaster.com/u/Jadzwin_ECUMASTER)\
**Post date:** [March 26, 2026, 12:32pm UTC](https://community.ecumaster.com/t/need-help-with-function-logic-for-aux-coolant-pump-control/5410/4 "2026-03-26T12:32:59Z")

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You need setup output in pwm function and select PWM function as a water pump.

Please refer to help for ewp