2000 montero sport with no ground to fuel pump relay. Is there an interlock associated with this ground?

 

don't know. is it inter-locking you out? or are you just curious?

 

without a ground on the relay coil the relay doesnt close so the pump doesnt come on. the ground is switched in the computer somehow so i thought it may be some sort of interlock.

 

You have both a fuel pump relay and a module in this vehicle to be concerned with, the relay powers and the module; the module passing current and ground to the pump. The relay is mounted in the passenger side foot well area, behind the carpet of the center console just below the radio area. It is attached to the MFI relay as a paired unit.

 

oh right.
My guess is its a negative trigger relay, so the comp sends negative signal to trip it.
Could be bypassed easy enough.

 

what would keep the ground circuit from being completed? would it be safe to bypass?

 

a relay is GENERALLY on the positive side of the circuit. It uses a negative signal/trigger of low current, to switch the positive high current.
By grounding out the negative trigger, the relay is always 'switched on'
Google "how does a relay work"

 

i know how a relay works im wanting to know why the ground is not switched on. theres got to be a reason for this. is it an interlock that is working properly and keeping it from working to protect the engine or is it supposed to be working? i can ground the relay coil and the pump runs and the engine runs until i remove the jumper then it quits. should i just ground it and go on or is that a bad idea?

 

id probably hook it up to an 'on' circuit, so only runs when the key is on.

Check the unit that is supposed to be sending the negative trigger (module, pc?), sounds like thats whats faulty. Kinda like where we were in post #3.

 

where is this located and how do I find an on circuit to ground it to?