Originally Posted by
chrisa3
Gonna have to get a sparky to have a look as my understanding of auto electrics is limited
Is there any reason why the new relay would trigger the pump with no ignition on. If I touch the + wires at the battery and only the - wire from the new loom, the pump starts. If i conenct the negative leads from the car first and then the negative lead from the new loom it doesnt.
Anyway, now the system is pressurised it starts on the key and runs, but I suspect its because there pressure there and it will just cut out after a while. Its tight in the garage at the minute, will have to try again tomorrow.
No, the new relay should be open contacts across 30(battery) and 87(output) unless you have BOTH a live at 86 and a earth at 85, it is obviously getting some stray voltage from somewhere for this to be happening, unless it is a very cheap relay, some can be super sensitive, had a few over the years, one of the ones used on spot lights on a car I had would stay on once switched on, a light tap on it saw it turn off, you could have one like this.
tabetha