Probably looking for an answer from CharlieX. Is there an easy way to determine if the ECU remains "on" after engine shut down.
Yep i think we're saying the same thing, if the temp's are above the threshold for the recirc pumps, the ecu stays on, but if they're not it turns off after 15 or so seconds.
There would be no point staying on and monitoring temps at low temps for it to reach 230F since that'd be impossible.
it'll stay on for about 20 minutes at most.
totally agree on that one, its problematic for me because its possible to get the ecu into a state where you can't turn it off without disconnecting the battery.
i'm not by my bench ecu but when i am i'll see whats lit up when its on.