engine intermittently cuts out at low revs and idle.

[Lingo79]

I have a 2012 custom 2.2l, which typically will play up more from a cold start. I wondered whether it was a ECU issue and replaced this with a cloned one, with no success.
when the engine cuts out there is a click from under my seat in the battery tray area. I had also wondered about the alternator, as voltage reading was erratic and high, so replaced that (as having checked it didnt seem to be a high enough rated alternator for the stop start - which also does not work - dash message when engine dies, asking for a manual start. the new higher amp alternator i fitted now won't throw any charge out. the LIN line into it only throws out an 8V output - read this is possibly not giving the alternator the signal to kick in with its charge?
other symptoms include: Any turning on heating or drawing extra power whilst idling tends to initiate the engine cutting off.
Whether this is related - back lights on central radio control can flicker and some of the buttons will be missing their light.
Random warning messages come up on the dash.

I had also tried running a jump lead from negative batt terminal to engine case, to check whether it was an earth issue, but again no joy.

Any thoughts greatly appreciated.

[metalworker0]

Stab in the dark .. on the clutch pedal should be a switch that detects when its pressed and operates anti-stall feature, that momentarily increases the revs to prevent stall .these have been known to fail

alternator i think is a smart alternator, how these work is a bit of a mystery to me .. as sometimes giving full output over 16 volts and sometimes switched off .

The stop start system will not work if batteries are below a certain capacity --- 80 percent ? and as far as i know , has to be a special battery -- called an AGM.

Worn ignition switches are a common to fail .. and work intermittently when this happens .

i take note whats going on, listening and watching youtube videos .. mainly american vehicle repair businesses who put the word out . ... and that is, a lot of replacement parts these days are made in china ..they either work or don't work when new or fail soon after, some of the businesses are experiencing a 50 percent failure rate on new replacement parts.

To do a proper diagnoses you need to scan it .

if you had forscan ..it may help lead you right to the fault.

Forscan - that's what they recommend here .

NOTE: you can use forscan to get correct fault codes with proper explanation of them - a generic fault code reader may be somewhat misleading, or doesn't work

"Forscan" is FREE software" that you download to a laptop..you buy the interface cable -- this is just the cable, you need a laptop)
You can join the forscan forum ..again free, to get the software and more answers.

https://forscan.org/forum/

Then you come here list the fault codes here ..and we will try to work out the problem.

all the best.mark

[Altransit]

A relay in the battery fuse box signifies that you have two batteries

You don't need a high output alternator for stop-start, but you do need a very good, fully charged EFB or AGM battery (or batteries?)

[Lingo79]

ok thanks for the replies - Forscan and battery tests next.....