Fuel pump wiring mod.

I need some help regarding the fuel pump wiring mod. After changing my mates carpet on his 20vt last week the car now refuses to start. A quick look last night
And we've got no fuel pump. I started checking the usual ( inertia switch, relays and fuses) to find the pump has been directly wired from the battery, past the pump relay and along under the passenger side carpet. I'll be going over tonight with a multimeter to check continuity and voltages but I need to know whether that mod is intended to work in conjunction with the existing relays, fuses and inertia switch or bypass them completely.

I can't answer your question as I've not done/seen the modification but here is the link to it......

https://www.fiatcoupeclub.org/forum/ubbthreads.php?ubb=showflat&Number=1103763#Post1103763

Hope it is of some help.

Thanks Rob_78. That did help. And thanks barnacle for the write up.
So the fuel pump mod uses the original power supply to switch a new relay that is providing the direct feed from the battery. The problem in this case was the new earth to the fuel pump was routed under the boot carpet and bolted to the 10mm nut holding the seat back. Just didn't notice it when I took the seats out.

Glad you sorted it!