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Weird PWM related behaviour


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I have an intercooler pump PWM wire on Aux 2 set to GP PWM with condition of IAT > 10C. When I switch the ignition (pos. 2 pre-crank), the pump start circuilating the water and all seems good.

However, when I switch off the ignition, the pump continues to operate. So I'm thinking the pump is the culprit and rewire the relay to feed on ingition switch (as well as battery) unlike before when it fed on battery only.

Do the same test - all good, I can switch the pump off now on the key. So I move to other area of the ECU config and want to temporarily switch the pump off from within the ECU, so set the IAT > 100C but now the pump won't stop.

I saved and uploaded the file, I played with various frequencies but my success has so far been intermittent.

It appears I either have a faulty pump (it is new) or PWM signal keeps coming even when conditions are changed.

I supposed I could scope the signal coming out of the Aux 2 and see if it's changing with conditions but other than that, is there a log I can check or monitor the output within PCLink?

Any ideas are welcome.



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