FIA Battery Isolator not killing engine

[ThanasisPolitis]

Hello all,

 

I have fitted an FIA engine kill switch and I am having a small problem.

the switch works when the alternator is not producing any current.

however if the alternator does produce current the switch does nothing…

this is how the switch has been wired up.

any ideas???

 

Edited August 17, 2024 by ThanasisPolitis

[phaeton]

Either the wire on 2 is the wrong one, or the coil is getting a 12v from elsewhere.

[IanS]

What ignition system have you got?

[richyb66]

Does the yellow wire go to the resistor?

Is the other side of the resistor connected to a decent earth?

Did you disconnect the wires from terminals 1 and 2 and bell out the contacts to verify which are open and which are closed with the switch on and off?

[ThanasisPolitis]

Hello all thank you for the replies!

I have run the wires myself so they go where they supposed to go and made sure the gauge is the correct one.

the ignition system I use is an Accuspark “Digital Ignition System”

The yellow cable indeed goes to the included 3.3Ω resistor that was included in the kit and goes to a descent ground on the engine/clutch cover.

I have also bench tested the isolator before installing it and it checked out.

this seems to be happening when the alternator is producing power so phaeton, you are right, the coil must be getting power from somewhere but I am not sure from where…

 

Edited August 18, 2024 by ThanasisPolitis

[ThanasisPolitis]

Could it be the ignition key switch?

it is the only one that has the alternator (KL30), starter motor and ignition coil (KL15) on it…

Edited August 18, 2024 by ThanasisPolitis

[ThanasisPolitis]

I think I have some wires mixed up…

based on the diagram below, on slot two it should be interrupting the COIL line that comes from the ignition switch and goes to the coil +

My connectivity, slot two interrupts circuit 50 from the ignition switch to starter as shown in the diagram below 

[ThanasisPolitis]

Hello all, I managed to solve this and the switch was wired wrong and instead of switching the coil, it was switching the starter motor!

Must have downed couple of pints before I did that switch… I have no other excuse for it…

Thank you all for your comments and help allowing me to see through my mistake.

[Darrell]

well spotted, glad its all sorted