GPS remote immobilisation feature. Wiring issues.

[English Fellow]

Hey all, thanks for having me.

I'm fitting a GPS tracking system into my van (Renault Trafic 2005, 1.9l Dci) and I'm trying to install the imobilisation feature. Once wired in it will let me remotely disable the fuel pump.

However, I'm struggling to get any information on the wiring of the fuel pump. I've chased what I thought were the wires for the fuel pump from the pump as far as I can but they get inaccessible past the bulkhead. However, these ended up just being the fuel level sensor wires. There seem to be no other wires coming out of the fuel sending unit for me to chase.

Ideally, I want to find the fuel pump relay so I can simply tap into that, but I can't find any documentation or guidance on where the fuel pump relay is in my van. Is there a way of tracking this down by brute-force testing of relays? Is there another/better way for me to wire in this immobilisation feature? (The tracker unit has a NC relay which is ideally wired in just before the fuel pump relay. When a signal is sent to the tracker by myself the relay opens and the pump shuts down). From what I've read, fuel pump relays tend to be under the dash or in the footwell as opposed to in the engine compartment. There's two under the drivers side dash, is there a way of determining if one of these is for the fuel pump?

I'd assume that disabling the fuel pump is the safest way to go, if I cut all power to the ignition then everything shuts down and could cause a gnarly crash.

Really my main questions:

Does anyone have any experience in working with the wiring of fuel pump on my vehicle and can point my in the right direction?

Is there a better way to go about installing this feature other than tapping into the fuel pump wiring?

Can anyone point me in the direction of the wiring diagrams for this vehicle, I've seached and downloaded some .ISOs that didn't work?

Many thanks, any help would be much appreciated!

 

[snowhead]

I'm pretty sure the Renault / Vauxhall DCI doesn't use an intank lift pump, it has a low pressure suction stage within the High pressure pump mounted on the engine.
As a result there won't be a pump relay.
The fuel rail near the injectors has a fuel pressure sensor, I suspect if you break the connection to that the engine won't start.
It should be easy enough to prove first, just unplug the connector and see if the engine will start.

 

[Vortigern]

Would it be easier to put the off switch on the ignition circuit?