Peugeot 206 cut out

Just to clarify , engine is not turning over ? What voltage at battery ?

no engine not turning .starter motor spins but not connecting to flywheel . battery at 12.9 volts .engine turns when u put spanner on crank pulley nut and turn it

Double check wiring to solenoid and check earth strap from engine to bodywork .

You'll need to follow my reasoning here,
you state the crank turns on a spanner?
Good now remove the starter and it'll probably take two here,
Get assistant to turn the crank while you either look/feel the flywheel teeth to see if they're actually moving/rotating.
My reasoning is there's no crank angle signal being generated as the flywheel isn't going round,
When running or the starter spinning.
I have seen in my time at least two vehicle that had somehow the ring gear had become loose,
Granted they "K" series engines/gear boxes that had the ring gear actually "GLUED" ON!! from the factory.
Until it became unglued.
But I have also seen all flywheel fastening bolts sheared off!!
So like I state you need to see if the ring gear turned when the crank is turned by spanner/socket.
This will only cost you some time to check.

Bit right field suggestion .If looking in oil cap and engine not turning, cambelt snapped ?

Ok granted my theory sounds wild but it based on solid logic.
Vehicle cuts dead and then wont turn over.
New starter fitted and still wont turn over,
Flywheel teeth appear fine so I'm left with the flywheel not turning over the crank when spinning over so no crank spin would mean no CAS signal.
Therefore I'd check the flywheel is still connected to the crank.
As stated no cost test,
The best kind to rule something in/out.
And I just remembered an xr4i that came in to me for a starter fault and to be honest pure luck when changing it revealed the flywheel MOVING!
Grabbed a screwdriver and moved the teeth,
Any long story short this V6 had snapped the crankshaft clean across.
I have seen some strange S***T in my time so I like to fall back on no cost test at the start.

thanks will check flywheel as sugested

i have to say it does sound like cambelt has snapped if it is turning over quickly its due to no compression .when cranking does the alternator belt turn?

Either one or the other.

of course

from beginning. I hit a curb got to 45 mph when engine suddenly cut out all ignition lights came on in gear foot 2 floor didn't bump start shifted to 3 rd gear engine didn't re start stopped turned key all ignition lights as normal starter motor spins engine doesn't turn over , battery good new starter motor spins but doesn't turn engine .spanner on crank engine turns cam belt tight so good .if u have any ideas let me know please I haven't a clue think volt drop

it seam as starter motor isn't exstending to flywheel as flywheel appears fine as I haven't a clue and mechanics ive asked don't know ime realy need help with this

Have you actually examined cam belt ? Cam belt might be " tight " but teeth on belt sheared off .Can you see camshaft turning when turning engine by hand ?