Wiring extra PIR to Floodlight with built-in PIR

[Nigel24]

I want to place a new PIR *inside* my porch so the outside Floodlight comes as I open my front door from inside - to light my steps - rather than when I'm already half way down them.
The Floodlight already has its own PIR which works fine when approaching my steps from outside.

How can I wire this independent PIR to the Floodlight without interfering with its built-in PIR ?

 

[EFLImpudence]

You will need a 3core & earth cable or flex and some sleeving for

Permanent live - BROWN
Switched live - BLACK, sleeved with brown
Neutral - GREY, sleeved with blue
Earth (CPC) - bare wire, sleeved with green/yellow

Connect to new pir as per instructions.
Then run cable to existing pir and connect to same terminals as the existing lamp. The existing lamp may be wired in old colours. red for brown and black for blue.

Permanent live - BROWN to brown or red
Switched live - BLACK to a little wire coming from inside the pir and going to the light, probably white, to which the original cable will not be connected.
Neutral - GREY to blue or black
Earth - bare wire, sleeved with green/yellow

EDIT - sorry, got my colours muddled. corrected.