fuel pump switch

I want to install a on/off switch for my fuel pump and I'm wondering if this would be the correct way to wire it. I'm using a 12V 30A 4 pin relay.

1. Cut wire between fuel pump relay and fuel pump. Connect wire ends to the 4 pin relay.
2. Connect ground to relay
3. Give switch 12V and connect to relay

Should I install a 30A fuse between the Fuel pump relay and the relay I install, or is this not needed?

Thanks

Why do want/need a switch to your fuel pump, your key is the switch :confused:

If you are going to install a switch though all your going to need is one relay, you can reuse the old relay or take that one out and install your own.

1. Give relay 12v sorce from the battery
2. Wire 30A fuse between 12v and relay
3. Make a new ground for relay in trunk
4. Connect fuel pump to relay
5. Connect switch to relay
6. Wire 5A fuse between switch and relay
7. Give switch 12v sorce form battery

Now the fun part is going to be the switch, because the ECU controls the fuel pump your going to need the ECU running off of that switch too. If you don't your going kill the life out of your fuel pump and your ECU won't be able to lube the injectors correctly.

To tell you the truth I started this myself and a month later I finally got everything wired right, I want to say the best thing to do and I regret not doing it was to leave it alone but just rewiring the fuel pump relay to the battery and move the ground to better spot

I want to install the relay and switch as an anti theft measure, I should have made that more clear. I want it so that when the switch is off the relay is not energized so the fuel pump will not have power. If the switch is on, the relay is energized and the power goes through the relay to the fuel pump.

Ok, well then thats easy. You won't even need a extra relay, just cut the 12v wire that has the fuel pump safety switch installed inline and add your switch or the wire that turns on your fuel pump relay

That wire has a low amp rating to begain with that you wont need a relay and the switch will handle it just fine, just make sure the switch you find has a ground.

Or if your after a theft safety idea you can open up your steering columm, if you look at your ingnition switch you'll see a dark blue wire come out. If you splice that and install a relay w/switch the starter will never work, but the fuel pump idea is ALOT better.

Even I've been able to hot wire my TC when it didn't want to start

Thanks. I'm going to install the relay just as a safety measure.

I think your missing the point, Ford already installed a relay for you as a safety measure. If you do that and something goes wrong your going to have a fun time finding the real problem, try not to make things complacted for yourself but instead keep it simple

So you don't have to run wires every were when you find out what color the wire is your taping into you can pop off the kick panel to the ECU and you'll see a bunch of connectors, you should see that wire built in with one of them.

I have a pretty good understanding on how the fuel system works. I have had to diagnose a bad fuel pump . I don't think this would make it all that much more difficult to diagnose if something were to happen, just one more relay to check. I just don't like the idea of all the power going through the switch.

As for taking off the kick panel to verify, colors can fade and become hard to distinguish between each other(as I'm sure you know) so I prefer something like a continuity test.

Thanks for all your replies, you been really helpful.

The fuel pump is already on a relay. The relay is activated by the ECU, so there's only milliamps on the line to the relay anyway. Just put a switch in the line from the ECU to the relay, it won't see any "power". As said, you're over complicating your solution.