Is there a way to use a 2 pole live switch to also switch earth at the same time

Basically on a BEC I want to use the momentary push start button to switch the earth to the clutch

Need to trick the ecu into thinking the clutch is in.

Can't permanantly earth it as then the second injectors won't fire.

Cheers Gavin.

Hayabusa? I have had this on other Suzukis before and just used a relay fired by the starter circuit.

HTH

Mike

A double pole momentary swithc should do the job - can't find any push button ones but a toggle like this would be the one.

Wyn

This one??

Hi Mike is a zx10.

Sorry to be thick but how do I switch an earth through the relay.

Diagram would be good.


Wyn the dash is all finish with a push button so would rather try and keep it if possible.

Cheers.

[Edited on 28/3/11 by gavin174]

Gavin - a relay is probably your best option I would say - I can draw up something when I get home if Mike doesn't get back to you.

Wyn

relay 4 pin required

Term 86 earth and link to 30 term
term 85 to switched pos side of momentary switch
term 87 to clutch switced neg cable

or use a savage push to start switch with 2 sets of contacts. One set fotr the start and one to switch the earth

[Edited on 28/3/11 by omega 24 v6]

Thanks for the quick replies.

Off to get a 4 pin relay now.

If this is going to be connected to the ECU I would make sure to use a relay with either a diode or resistor built in to suppress the back EMF which is created when the relay is de-energized as your ECU may not like having a couple of hundred volts poked up it's bum

While the wiring suggested above will work the coil is technically wired backwards, doesn't matter with a standard relay but it does with a suppressed one.

Correct wiring should be:
PIN #85 - Earth
PIN #86 - Positive from Start Switch
PIN #87 - Clutch switch wire from ECU
PIN#30 - Earth

Regards
Davie

I always get confused with 85 and 86 terms as we never tend to use relays with diodes or resistors at work. As Davie says my wiring will work but he does have a point re the emf and the ecu.

[Edited on 28/3/11 by omega 24 v6]