Start/Stop has stopped since MOT E91

[eatontrifles]

Since I had my MOT test done three weeks ago (passed with no advisories, thanks for asking) the auto stop/start hasn't worked on my LCI E91. It was working fine before. Part of me is glad, but like the lovable rogue that it can be, a part of me is missing it.

I know there's certain conditions that need to be met but it should all be fine, I've done four long (over 200 miles) trips since so the battery has easily had a chance to sort itself in case it dropped a bit during the test. No warning lights on the dash etc.

Any ideas? Would the MOT place have disabled it somehow?

[eatontrifles]

Thanks for all the responses. The garage is just an MOT place rather than a dealer or indie so I doubt they'd have anything sophisticated diagnostic-wise.

The outside temperature occurred to me as well but it's generally been over 10 degrees until this week and after a 6 1/2 hour drive to Cornwall a couple of weeks ago it was up around 15 so I don't think it's that.

How would I go about seeing if the system is functioning? I don't have a laptop diagnostic tool although it's something I've been thinking about getting if anyone knows of a lead/software combo that would work?

Nothing else has changed from 'normal', it before the MOT either by the way - it would still function with the air con turned on etc.

[eatontrifles]

Spoke to the MOT place today and they confirmed that they wouldn't have disabled the system save for pressing the button on the dash. They've offered for me to pop in on Saturday morning and they'll plug in their diagnostics kit & see if anything is flagged up that might be causing it.

[eatontrifles]

The car was plugged in this morning and checked over at the MOT garage who confirmed that the system is showing as active and the usual parameters all look OK - clutch, gearbox & brake pedal sensors etc and no ECU errors other than brake pads from when I replaced them a few weeks before the MOT.

They suggested disconnecting the battery for ten minutes or so might reset the ECU and reboot the system in case it had got confused for some reason. Any more thoughts?

[eatontrifles]

Three and a half months on and yesterday, the stop/start reared its head again and appears to be working as normal. I can only presume that something during the MOT test spooked it and it has taken this long or that many engine starts to reset back to functionality.

Merry Christmas!

[eatontrifles]

Jon1967x said:

If you've not tried, I'd manually disable and then enable it again a few times and give the car time to both warm up and fully charge the battery (I imagine on an MOT there's a lot of time sitting there with just the ignition on)

I tried all that kind of stuff on mine, leaving it untouched or off for whole journeys, on and off numerous times and I went on many long journeys without any change. It just suddenly started working again.