My tacho currently doesn't work but I was hoping to try and get down to the drags on Friday night anyway. Since my E6X has the ability to drive a shift light I thought I might try and knock one up. The thing is, even though I can wield a soldering iron, I'm a total electronics gumby.

What I have is an output on the ECU that I can set up so at a user-defined RPM speed and above it will become an earth. (or as the manual describes it: 1A continuous pull to ground).

Given that, what is the simplest but safest/most robust, circuit I can build to turn on a bulb or LED. Should I use the ECU behaviour to switch a relay, or can I just wire my light straight up and switch it directly from the ECU?

Is there a Jaycar outlet near you? They have some good kits.

Frequency switch kit: switch devices on or off from a pulse output. Good for setting a shift light. Cat: KC-5378, $35.95/kit

Rev limiter / shift indicator kit: 3 lamps (2 green, 1 red), plus limiter function if your ECU supports. Cat: KC5265, $34.95/kit

Digital Tacho display kit: PIC based. Can mount the box anywhere, reads up to 9,900rpm. Cat: KC-5290, $62.95/kit

Or you could just get the automotive ****ion multimeter (QM-1440) for $49.95, plus it would come in handy for other tuning duties. It does a number of handy things like Dwell test/adjust, idle/mixture, PCV test, dizzy advance, Alternator output, alternator diode test, etc etc.

Best of luck with it Brendan.

You've already got your 1 amp ground.

Connect your shift light up to 12v (with 1 amp fuse for safety) and the other side up to your E6x output

When your E6x output is triggered the circuit is complete and the light will come on.

If you want to run more devices than this off the same trigger, use a relay. Or if you have any issues having that live 12v line running through your car use a relay.

Dont forget the fuse

Or ensure the line is fused somewhere

Peace

Tim

Thanks guys. Ended up finding a guy at work with some know how. Stopped by the Jaycar on the way home from work, did a bit of soldering, and now have myself the world's dodgiest shift light. Just gotta splice it into the E6X and I'm away.

haha dodgy

sif not buy one of these

:D http://www.haltech.com.au/shift_light.htm

haha dodgy

sif not buy one of these

:D http://www.haltech.com.au/shift_light.htm

hehe there was a method to my madness...

I wanted something quickly so I could race at the track tonight, even though slack arse Dallas didn't make it up here to fix up the mapping and make my tacho work. And the genuine shift light wouldn't have got here in time. Besides, how big is that thing?! The one I've made just uses a single tiny 3mm red LED (http://www.jaycar.com.au/productView.asp?ID=SL2644&CATID=&keywords=bezel+12V&SPECIAL=&form=KEYWORD&ProdCodeOnly=&Keyword1=&Keyword2=&pageNumber=&priceMin=&priceMax=&SUBCATID=) triggered by a relay. Much tidier!

Haven't had time to wire it up to the car yet, but the circuit works a treat.

As it happens, I won't be racing tonight anyway.. not least because my parent's neighbour backed into my car while coming out of her driveway. Doh :tantrum: