My Scorpio-N's engine refuses to shut off: ASC remains clueless

I am trying to understand what could cause this issue.

BHPian Pradzz recently shared this with other enthusiasts.

I am asking this on behalf of my Brother-in-law (who is not a part of this forum).

From the past few weeks, I have noticed the engine on his Scorpio-N Z8L diesel AT doesn't turn off as soon as you press the start-stop button (transmission in Park and Handrake engaged). Initially, I thought it was a one-off case since it wasn't happening every time. Later the issue became more apparent and it would normally take 3-5 secs after pressing the button to turn off.

Today however, he travelled form Mysore to Bangalore and after he reached, the engine refused to turn off for 15 mins. Finally, he engaged Auto Start-stop (he turns it off everytime he uses his vehicle as it gets very annoying in traffic at times) which in-turn turned off the engine after a few secs. There were no errors on the speedo console according to him.

The issue started getting worse and he lodged a complaint with Mahindra. They sent someone to check it.They found no issues, it was switching off like normal. My BIL asked him to drive it for like 5-10kms and then check. It took ~4mins to stop.

The vehicle was then taken to the Service Center in Bangalore (Shreesha I think). After messing around for a bit, they said it was the start-stop button that was faulty and that it had to be replaced. But that would take like 5 working days. My BIL pulled some strings and sourced one from Mangalore's Karnataka agencies (I think) and the button was replaced. Yesterday they tried everything at the service center and it was absolutely normal.

Today while on the way from Blr to Coorg, the vehicle refused to switch off at Hunsur, it took around 4-5 mins again. They were advised to keep the key fob close to the Start-Stop button and it worked. After reaching Virajpet, the car just wouldn't turn off. At this point, the key fob thing was found out to be a fluke thing or a co-incidence and it wasn't working. Now the Auto Start-Stop wasn't killing the engine anymore either. He was on video call with Mahindra for around 45 mins and nothing worked. Finally, he was asked to pull the battery cable, which stopped the engine. This is a serious issue and the vehicle will be sent back to Mahindra in Bangalore next week.

I am trying to understand what could cause this issue. Have you encountered a similar issue or know someone who has? Can you think of anything that can cause this? Please do let me know. Any help / leads are greatly appreciated

Here's what BHPian KumarS had to say on the matter:

Indeed this is first time I have heard of this issue.

I am wondering if adrenox could be used to turn off the engine.

I see the vehicle is Z8L so this should work.

Read BHPian comments for more insights and information.