Ignition barrel problem - bypass with push switch?

langdang

Hi, looking for some advice:

will have a poke around with a multimeter later but I have an issue with my starter motor circuit. If the culprit is found to be a dodgy ignition switch (I suspect it is) rather than a dying starter or sticky solenoid - can I just fit a momentary/push to make switch in parallel with the ignition (starter) switch part of the ignition barrel?

EG http://www.maplin.co.uk/Module.aspx?ModuleNo=34858

The ignition barrel is fine for the first few clicks, it switches out the radio etc when twisted as far as "start". I can hear a relay switching (internally in the cabin I think, switching off the radio etc), but nothing happens under the bonnet - no noise or activity at all from there.

For the last while it would start if you kinda jiggled the key in the start position but it's taking longer and longer to get the starter engaged now.
It'll leave me stranded soon.

Is the pushswitch (above) in parallel with the "start" switch in the ignition ok?
Will the "engine start" circuit only work when the ignition barrel is switched to start, or if I hit the button during normal running would it try to engage the starter?
In other words, does the radio etc have to be switched out for the starter to be switched in?

Would I need a relay in this circuit? It obviously won't be handling the full power of the starter but what's flowing in through the ignition switch during starting normally?

1999 Mazda 626, ie old, simple, no fancy electronics etc to worry about, stringing it along as far as I can on as little as I can responsibly spend on it.

langdang

She's starting on the button now

Slidey

Just like a new Lexus so!

Bigus

depends on the way you wire it.
I'd do a simple wire from the battery through the button with the other end wound around solenoid connection. See how you go and then get all fancy wiring it to not work when ignition is off when you get the chance.

langdang

Bigus wrote: »

depends on the way you wire it.
I'd do a simple wire from the battery through the button with the other end wound around solenoid connection. See how you go and then get all fancy wiring it to not work when ignition is off when you get the chance.

It's working fine now, just took off the steering column plastic and poked away with the multimeter (no CANbus or anything complicated to worry about). I could see that I had 12V on one side of the switch but the switch was obviously dodge because it took a good bit of jiggling etc to get 12V at the other side.

When you turn to the first click there is no power to the starter part of the ignition switch.
When you turn to the second click you do have 12V at one side of the switch so it's possible to start the car without switching out the radio and other accessories, but not really the best way to do it.
Once you turn to the start position you switch out the radio etc so all the battery power is available for the starter, gentle push of the button - starts, leave off the pushbutton and the key.

I probably could have put in a relay to make it less of a fudge, but it works...
I did make a mess of drilling the steering column surround to fit the switch, and I'm thinking now that a black switch might have been better. The red switch is just too much of an invitation to scum. It won't start without the immobiliser chip in the key, but try explaining that to someone who wanders around with their hands constantly down their tracksuit-pants-tucked-into-their-socks.

mgbgt1978

You should have no problem with the NCT either (as far as the switch is concerned).
They will only want to confirm that the key switches off the engine.