Relay 7 blower, What feeds the negative wire?




Rangerover 1997 4.6

If i bypass the relay the blowers work fine but otherwise they dont work.There seems to be an issue with the negative feed to the relay?

Conector c174 - The blue 8 pin connector that plugs into the fuse box and goes to relay 7 - The positive side seems ok but i have put a multimeter to the wire white/light green which i believe is the negative wire that activates the relay and im getting an neagative output that slowly increases but not enough to activate relay 7 - Can anyone advise what sort of voltage should be coming through when the ignition is on and where does the negative come from, eg becm

Next step i think is to dismatle the fusebox and solder, But i want to make sure what feeds the negative wire?

Its getting late,not had supper but wine is here - hence fuzzy answer !
The BECM provides an earth path to pull in the blower relays,from memory its often a corroded wire between the fusebox and BECM.But its a few months since I did one.All I'm saying is check the wiring before you start trying to rip the fusebox apart.

I dont think it the fuse box because ive put a multimeter directly to the White/L Green wire which i believe is the negative and get the same readings as through the fuse box. Do you know the routing for this wire? should i be getting a solid negative 12v feed if i connect the positive end of the multimeter to the positive and the negative to this wire when the ignition is on?