Finding ignition power under the bonnet

[Winnie]

Hi all,

Just installed an intercooler with a fan under the bonnet and am looking for a wire that has power only when the ignition is on, I want to have it off when the key is switched to accessories and on when the car is running (or key in the ignition position). This wire will only be switching the relay so will draw very minimal current.
Read somewhere that I should find a wire in the wiper motor but when I tested them all it came on with accessories on, so would flatten my battery pretty quick if I was listening to the radio.
Any ideas on where I could find a wire as described? Would appreciate any suggestions.

Regards,
Chris.

[MudRunnerTD]

You could run one back out through the fire wall from the cig plug?

Are you just going to have an on/off switch Chris or control it via a thermostat switch?

If its just and on/off then fit the relay inside and power up from inside then from your switch to the relay too. Then a single wire out to the fan from the relay. Earth the fan on the bonnet.

Or.... Ol' mate Yendor is your man mate.

[Winnie]

Cig plug is on when accessories are on... why should I fit it to a thermo switch? I figured I might as well have it running all the time? That's the way CC say to install it.

[MudRunnerTD]

Cig plug is on when accessories are on... why should I fit it to a thermo switch? I figured I might as well have it running all the time? That's the way CC say to install it.

Yeah I have switched mine and use them only occasionally. Mine is a Water to Air (WA) cooler and I have switched the pump too. But I like switches ;)

Hmmm... Mate I have absolutely No Idea what accessories only run when the ignition is ON and not when the Accessories are On??

Sorry one for Rodney for sure

[Winnie]

Really? Why would you ever want to turn the water pump off?

[Drewboyaus]

What about at the fuel pump relay?


Tip tip tip......tap tap tap....

[Ben-e-boy]

Its always in the last place you look.




Or the windscreen wiper motor on tne fire wall and very very close to the intercooler, thats where I run power for my water pump control.
But on the other hand I wouldnt bother with the fan. Its a restriction at higher speeds.

[MudRunnerTD]

What about at the fuel pump relay?


Tip tip tip......tap tap tap....

TD42Ts have a Mechanical fuel pump but bloody good call Drew for a Petrol. I could be wrong but don't think there is power there.

Winnie have a look under the relay cover beside the battery there may be something obvious there??

[Winnie]

Its always in the last place you look.




Or the windscreen wiper motor on tne fire wall and very very close to the intercooler, thats where I run power for my water pump control.
But on the other hand I wouldnt bother with the fan. Its a restriction at higher speeds.

Checked there and it still has power when key is in the accessories position.

[MudRunnerTD]

Checked there and it still has power when key is in the accessories position.

Is there a positive power to any of the other gauges under the bonnet? Wire going to the thermostat or oil pressure solenoid maybe?

[Ben-e-boy]

I still think the fan is waste of time, I will admit I am wrong if you are un able to manage egts in the slow stuff.

[Winnie]

Look I am only really doing it because it's there... not worth the effort to remove it really. So might as well wire it up.

[liftlid]

Diesel fuel pump has a solenoid wire on it, have a switch to turn off fan when not needed, winching etc, I have my fan working for low speed cooling, figured the restriction didn't matter at high speed, pick an accessory wire under dash

[Yendor]

For an ignition feed you will need to run the wire inside the vehicle to the fuse box.

[Winnie]

Okay so I should be able to find something behind the fuse box there? That should be simple enough.

[Yendor]

I would connect it to the protected side of the fuse for the instruments.

[Winnie]

Thanks for the info Rod, I will have a play tomorrow and see what I can come up with.

[liftlid]

Okay so I should be able to find something behind the fuse box there? That should be simple enough.

I ran a accessory and an engine on wire from the back of the fuse panel, put them through a inline fuses then switch and use as a control wire to switch relays, if I remember correctly there are spare lugs on the back of the fuse that will take spade lugs, has anybody else seen this?