From ex Auto sparks [ retired now 13 years ] fully conversant with Bosch "K & KE" system...What you have hear is the Pump is " locked up...siezed "...when you bridge the Relay out, the Pump draws 9 amp normal [ if 044 pump fitted then 10 amp ]...the 12v gets "loads up" hence your getting 9 volt...so the pump is Duff...but watch there is no "Rust debre" in the Tank, as for sure the Tanks rust in the inside over the years....removing the Pump should show this, so dont fit new Pump untill new tank fitted, of course it can be the pump has just siezed !!...hope of help. Peter