Electronic geeks - Corsa Sport - for Vauxhall and Opel Corsa B, Corsa C and Corsa D

Not logged in [Login - Register]

You Are Not Registered Or Not Logged In

Corsa Sport » Message Board » Off Day » Geek Day » Electronic geeks

New Topic

New Poll

<< 1 2 3 >>

Subscribe | Add to Favourites

You are not logged in and may not post or reply to messages. Please log in or create a new account or mail us about fixing an existing one - register@corsasport.co.uk

There are also many more features available when you are logged in such as private messages, buddy list, location services, post search and more.

Jambo

Member

Registered: 8th Sep 01
Location: Maidenhead, Drives: VXR Arctic
User status: Offline

30th Jan 12 at 10:11

Hmmm

Thanks Dan/Ed/Pow/Dom

How big would the board need to be? There is limited space on the tunnel.

Dan

Premium Member

Registered: 22nd Apr 02
Location: Gorleston on Sea, Norfolk
User status: Offline

30th Jan 12 at 10:14

You wouldnt need a board, just a relay

Adult GiftsClick here to vist us

Member

Registered: 10th Sep 03
User status: Offline

30th Jan 12 at 10:18

Would use one of these little relays:

http://www.maplin.co.uk/2a-miniature-dpdt-latchingrelay-37529?c=froogle&u=37529&t=module

Would be on a board not much bigger than your thumb - would put it on a board so that you can have some screw terminals for the wiring and a diode and voltage regulator so you don't damage the electronics in the switch as the 12v signal from the car is usually a bit 'dirty'.

Dan

Premium Member

Registered: 22nd Apr 02
Location: Gorleston on Sea, Norfolk
User status: Offline

30th Jan 12 at 10:20

Sounds a bit ott to me ed, its car electrics, not going to hurt that switch. Its designed to work in a car already.

Adult GiftsClick here to vist us

Member

Registered: 10th Sep 03
User status: Offline

30th Jan 12 at 10:26

It's designed to work on a car with a CAN bus with regulated signals. For the sake of a 15p regulator and a 5p diode, why not.

Dan

Premium Member

Registered: 22nd Apr 02
Location: Gorleston on Sea, Norfolk
User status: Offline

30th Jan 12 at 10:30

Still over complicated. The switch probably doesnt even have a can link go to it.

Ive wired hundreds of vehicle system items from scratch with no regulators or diodes, and never had a problem.

Your way will do exactly the same thing, just far to complicated for me. Each to there own

Adult GiftsClick here to vist us

Dom

Member

Registered: 13th Sep 03
User status: Offline

30th Jan 12 at 10:51

I don't think you'll need to supply +12 and -12, rather just supply voltage on one of the pins and it'll make when pressed. But as said you need to buzz the pins out and see what's what.

If you're wanting it to be push-to-stop as well then i can't see how you do with a simple relay setup as surely you need some sort of logic, hence the guy using a PIC?

Either way this has gone from a piece of piss simple press-hold start 5 minute job to a custom automated ignition system

Dan

Premium Member

Registered: 22nd Apr 02
Location: Gorleston on Sea, Norfolk
User status: Offline

30th Jan 12 at 10:59

I think you do need both, going by that link jambo posted.

Stopping the engine would prove a little more difficult, but certainly possible.

Adult GiftsClick here to vist us

Jambo

Member

Registered: 8th Sep 01
Location: Maidenhead, Drives: VXR Arctic
User status: Offline

30th Jan 12 at 11:30

Not everly fussed by push to stop... Got to remove the key anyway.

So was my idea a bit more simple using the plastic switch as a switch? Linked to a maplins job via wire? Is that not more simple?

Jambo

Member

Registered: 8th Sep 01
Location: Maidenhead, Drives: VXR Arctic
User status: Offline

30th Jan 12 at 13:15

I have one of these lying around:

The switch part ignore the big brass solenoid

[Edited on 30-01-2012 by Jambo]

John

Member

Registered: 30th Jun 03
User status: Offline

30th Jan 12 at 13:16

Stick that button under the plastic bit of your BMW switch, sorted.

Jambo

Member

Registered: 8th Sep 01
Location: Maidenhead, Drives: VXR Arctic
User status: Offline

30th Jan 12 at 13:17

If it fits.

Just got to try and illuminate it then

Or just give up and use an S2000 button

adiohead

Member

Registered: 28th Sep 01
User status: Offline

30th Jan 12 at 13:21

Put the button in as it is and just turn the key when you press it.

Dom

Member

Registered: 13th Sep 03
User status: Offline

30th Jan 12 at 13:43

I'm seriously confused why you're trying to make this more complicated than it is! I don't understand why you'd want to hack the housing and 'fit' a switch when it already has one that is perfectly suitable for the job

If it is as Dan says, then it'll be something along the lines of -

Feed +12v (take it from somewhere like the ciggy lighter) to pin 3 on the switch
Connect pin 10 of the switch to ground (ground being body work)
Connect pin 4 to one side of a 'big arse' (probably need something like 30amps, although the bloke used 16A relays on that post) relay, mounted close to the key barrel. You'll also need to supply +12v to this side of the relay as well.
Then you want to remove the connection to the starter on the key barrel and wire that to the other side of the relay along with ground.

Edit - If you want to illuminate the LED then you'll need to drop the voltage from +12v to +8v, which can be done simply by using a resistor (the guy mentioned 200ohms). However i would be inclined to regulate the +8v supply to prevent damaging the LED if there was a spike etc

Edit 2 - The guy mentions negative voltages for the switch and LED which I find a bit confusing, as i can't see the switch needing 24v to operate nor the LED being 16v. But if it is the case that you need negative voltages then you can easily throw together an 'intelligent' split power supply or you could use a resistor divider (rough idea - http://tangentsoft.net/elec/vgrounds.html), which is the crude way of doing it but both will give you something similar - ie: you feed +12v and you'll get +12v, 0v and -12v out.

[Edited on 30-01-2012 by Dom]

Jambo

Member

Registered: 8th Sep 01
Location: Maidenhead, Drives: VXR Arctic
User status: Offline

30th Jan 12 at 13:56

Im not trying to make it more complicated Dom i just honestly dont understand half of what you guys have written

lol.

If you believe that the chip inside the switch will work, then fine ill go that route. I had been advised it wouldn't/couldn't work.

So do i need a plug? For the switch off an E90 BM? Or can I solder directly to it?

Dom

Member

Registered: 13th Sep 03
User status: Offline

30th Jan 12 at 14:27

There's no 'chip' on the board, it's simply a hall-effect switch and LED combo along with a few surface mount resistors for the LED.

First thing i would do is make sure starting your car is simply the case of bridging the key position on the barrel and that nothing 'funky' (read intelligent) is going on.

After that and to save having to solder to the board, you'll need something like pcb pin header socket (either like >this<, although you get different spacing or pitch between 'holes', or if you have something like a PC motherboard header, like >this<; bit of trial and error needed) to fit into the backside of the switch.

Then, it's a case of marking which pins are what on the switch (usually they are numbered on the socket fascia) and the wiring it accordingly to a relay (>this< is probably OTT but it'll work, although i'd ebay it as that is pretty expensive).

You'll end up with something sort of like this -

Edit - Relay pins could be different depending on what relay you use.

[Edited on 30-01-2012 by Dom]

Jambo

Member

Registered: 8th Sep 01
Location: Maidenhead, Drives: VXR Arctic
User status: Offline

30th Jan 12 at 14:33

Thanks Dom, i think i got that!!

Dom

Member

Registered: 13th Sep 03
User status: Offline

30th Jan 12 at 14:40

Note that you may need a negative voltage on PIN 10 of the switch but i did mention how you can overcome that. Likewise, the LED but as mentioned i'd look at regulating the +8v supply for it anyways over just using a 200Ohm resistor - do a google, but something like >this<; C's being capacitors, D's being diodes, IC1 being the regulator which would be a 7808 for +8v (if the LED needs -8v then you'd feed the +8v from the regulator to a split power supplt/resistor divider).

Edit - If you haven't got a decent DVM then it's worth investing in one (useful if it has a 'buzzer' but otherwise you can use the resistance setting), as you really need to be checking over parts as you go along.

[Edited on 30-01-2012 by Dom]

Seany

Member

Registered: 13th Dec 06
Location: Dunfermline, Fife : Drives Astra cdti Sri
User status: Offline

30th Jan 12 at 14:48

Surely wouldn't cost too much to take it to an auto sparks and get them to fit it jambo?
I got one fitted to my old corsa for circa £40.

Dan

Premium Member

Registered: 22nd Apr 02
Location: Gorleston on Sea, Norfolk
User status: Offline

30th Jan 12 at 15:09

I doubt the led even needs to be 8v to be fair. All the LEDs I usually work with range from about 2v to 24v. Can't see where the car will be reducing voltage to 8v for the sale of lighting an led.

The diagram Dom drew is exactly as I explained earlier and that's what I'd do personally.

Id use a relay holder with proper crimped terminals and screw it behind dash etc.

Adult GiftsClick here to vist us

Dom

Member

Registered: 13th Sep 03
User status: Offline

30th Jan 12 at 16:09

Think the LED will be trial and error as i'm still unsure about the guy stating negative voltages - so 12v with 200ohm resistor feed the LED live pin will roughly give you 8v (if there LED is around 20mA). Chances are it'll probably work but as the car system is never 12v, can be a fair amount higher, and for the sake of a few quid a regulated supply would be the better option (would output 8v @ 1A with the nominal input being between 10.5v to 25v) - Simple 12v to 8v

Ian

Site Administrator

Registered: 28th Aug 99
Location: Liverpool
User status: Offline

30th Jan 12 at 16:15

So you have the momentary push to make on two of those pins?

Dan

Premium Member

Registered: 22nd Apr 02
Location: Gorleston on Sea, Norfolk
User status: Offline

30th Jan 12 at 17:05

I'd seriously not bother with a regulator. That's what the alternator does. Anything else would be overkill I'm sure.

It's not gonna hurt to add it, I just wouldn't.

If you want to supply me with the switch I can test it. Better still sort me the plug to go on it and I'll wire it with she'd loads of wire spare so u can see how it needs to be and then just wire it in

Adult GiftsClick here to vist us

Jambo

Member

Registered: 8th Sep 01
Location: Maidenhead, Drives: VXR Arctic
User status: Offline

30th Jan 12 at 17:08

Thanks Dan.

Ill see if i can get the plug and a bit of the loom, see if FAb will let me have a splice.

Jambo

Member

Registered: 8th Sep 01
Location: Maidenhead, Drives: VXR Arctic
User status: Offline

31st Jan 12 at 13:12