Hi sifus, please advise!

My water pump Grundfos CM3-4PM1 15 is running non-stop while am not using any tap water.

When I turn off the power switch and turn it back on, the pump starts running and the "pump on" light indicator is on. But a few seconds later the "pump on" light indicator turn off.

Checked everywhere and cannot find any leakage.

Consulted one of authorized service panel through phone calling and was told to replace a new PM1 due to suspect controller failure.
Is there anything to do with the built-in non-return valve that might causes the failure?

Did a survey new PM1 is costing around RM5xx. Want to know if any alternative OEM/ brand which compatible and lower cost? Thank you

This post has been edited by jw0987654321: Apr 8 2023, 04:46 PM

Surprisingly, I find my water pump is working well once again since yesterday. *scratching my head*
Anyway, thank you sifu for the advice! will definitely keep it in mind who to find when times come change a new one!