Peugeot 407 no crank no start

You can get a disk from "Emanuals online"
or Ebay.

Still as it's an auto it'd be a good idea to check the inhibitor switch on the gear selector.

Same as numeral safety switch ??

Inhibitor switch is usually on the gear selector,
Hidden inside the centre console

Inhibitor switch same as neutral safety switch on outside of box on some cars .

Your right,
I'm just old and thinking about series 1/2/3 jags.

I'm older than you and remember when it was all Borg Warner 3 speed boxes and I went down south for a week on a factory course !!!! If memory serves me right the inhibitor switch screwed into side of box with 4 Lucar terminals , 2 of which worked reverse lights .Those were the good old days !!

Can also remember some up at selector lever as you say .

Sorry to the O/P and for all this remembering of old days.
What I should have remembered is rule one,
As the O/P asked I should have checked the manual.
So Fuse 8 feeds down to the relay that triggers the starter motor,
check both,
After that the relay is triggered by the multi function control module 2.
Everything else runs from the Transmission control module,
So there doesn't appear to be any interlock switches.
So if it were here with me now I'd be running a diagnostic on the gearbox modules and controls with Diagbox. after testing for power and operation on F8 and the relay.

That's more helpful. If the fuse and relay are ok (will cheak tomorrow when I can get to where it's stuck) and there voltage to the starter b+ post and trigger wire then it's a faulty starter. Is that right??

I normally test suspect starters with a remote starter tool,
Which is basically two wires/clips and a button in the middle.
You can buy them but for a one off just pull the small wire of the starter and connect a long jump wire to the same terminal,
Now the other end of the wire you touch the battery pos+ and if the starter/wires are good it'll spin over.
Doesn't even need the key on.
BUT DO MAKE SURE IT'S NOT GOING TO ROLL.
I've seen people being run over by the car they're working on drive off un driven as it were.
'course if the keys in the run position and the starter spins it ought to start and run.
If not then it's electrical.