Installing FIA Battery Cutoff Switch

[Paul JA]

I've made progress on this, I've ditched the mechanical switch and gone for a Cartek GTS. This switches the battery 0V leg. It also needs a permanent supply and can switch up to 40A to use to control the ignition / ECU etc.

There is a fused 30A supply on the battery that feeds the under bonnet protection unit, if lifted this cuts the coil supply and a few other things. The only issue is that the hazard flashers come on when the supply is re-instated so needs a button push.

I have also identified the coil supply wire in the engine loom so if there's an issue I could use just that. The only minor thing is that the CarteK GTS would keep a permanent supply to the coil coil packs even with the ignition off. I could get around this by feeding the new coil supply via an ignition controlled relay.

 

[plugsandsparks]

Thats the one i use. When you switch it off, it cuts supplies to everything so no issue, current draw when off is very small but not insignificant so if the car is off road for a while occassional battery charging will be required. I use the 30A aux supply to feed the coil supplies, this kills the engine dead.

 

[Paul JA]

Looks like I'm on the right lines now. It will all be done when I rewire the battery etc to add a fuse local to the re-located battery and bigger battery cables (they are 'small' at the moment)

 

[Paul JA]

Thats the one i use. When you switch it off, it cuts supplies to everything so no issue, current draw when off is very small but not insignificant so if the car is off road for a while occassional battery charging will be required. I use the 30A aux supply to feed the coil supplies, this kills the engine dead.

So does this mean you have a permanent supply to the coils even with the ignition off as I assume you have used a +ve feed direct from the battery?

Any pics of the install ?

 

[plugsandsparks]

Yes correct, in a normal car this would have gone through a large relay triggered by the ECU. My car is only used in competition and occasional road use and most of the time the Cartek is off. To start the car , cartek on, ignition switch on, press start button. I have removed all mechanical relays for reliability and only used either a solid state PDU or solid state relays.

 

[plugsandsparks]

 

[Paul JA]

Out of interest what car is that and what do you compete in ?
Rather than rely on the bodywork I'm going to run a -ve cable back from the engine bay to the GTS that will be mounted on a copper bracket giving me decent connection point

 

[plugsandsparks]

Its a Cayman Rallycar competes in Motorsport News Circuit Rally Championship

 

[Paul JA]

This is the result, just a few more bits and the seat can go in