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Keyless ignition setup

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Hi,

I'm looking at fitting an ignition "toggle" switch to replace my cars keyed igntion.

I've seen that about 40amps is recommended for the 12v circuit.

However, I'd like to know how to work out what the amp rating is when other switches are listing a 240v rating. Could someone explain this to me please?

Thanks in advance,
Anthony
 
hi

not sure on working out the current dc current rating for an ac rated switch, but you could use any switch, and run the ign feed thru a suitable relay.

If this is a newer car then you may have problems.

This is a job that i have to do on a weekly basis (im an auto spark), and on modern cars can be a proper pain, due to the immobiliser fitted as standard in almost every car built in the last 10 years.

If this includes your car, then you either have lots of work to do to bypass the immobiliser, or you still need to put your keys in the barrell, thus negating the use of a switch in the first place.

(bypassing the immobiliser or key system will invalidate your insurance, unless you notify them before you start. if you notify them afterward, they may cancel your policy with immediate effect)
 
I'll be checking with the Insurance company before starting for sure.

My plan so far is to have the cat1 alarm and immob. still connected and running on the trickle feed from the battery master (isolation) switch. This will work the remote central locking. There is no factory fitted security on the car so I'm ok on that front as far as I can see. The battery master switch will be the "key" if you like and then the 40amp switch will be the turning of the key, then the start button will be the final piece in the process.

When you say I could run any switch but put it through a relay, how would this be set up, and what sort of relay would be required? I take it that it would need to be rated to 40amp, but I could run it of the 15A switch that I have details of below.

As for the conversion I mentioned previously, the figures I'd seen rated against a switch that had confused me were these:
15A 12 VDC
15A 125VAC
10A 250VAC

I wasn't sure how they were worked out. I gather that VDC is what cars use, and VAC is domestic supply.

Thanks for your help,
Anthony
 
Is your key a simple all-metal thing? If it's got a plastic end on it, try wrapping that part tightly in aluminum foil and then try to start the car. If it doesn't start, you're going to have to figure out how to get past the immobilizer.
 
Its ok I know this car pretty much inside and out and know 100% there is no stock immob. The immob. that is on it is on the Alarm as I had it installed after I got the car a number of years ago. I'm probaly going to re-wire the alarm when I've done this mod as I don't like the way they installed it. The wiring wasn't exactely "well done" to say the least, so I figure I'll strip it out, mark all the wires and redo it to my standards.
 
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