ECU & Coilpack wiring

[eon172]

I've hunted online but can't find a wiring diagram that covers this for a ph2 172/182, could anyone share one? Or otherwise confirm any of the many sellers of manuals (dvds) on eBay that include a reasonable set of these? Cheers.

 

[NorthloopCup]

I've hunted online but can't find a wiring diagram that covers this for a ph2 172/182, could anyone share one? Or otherwise confirm any of the many sellers of manuals (dvds) on eBay that include a reasonable set of these? Cheers.

What info in particular are you after mate?

 

[eon172]

Hi Mark, trying to understand the right place to pick up the ignition pulses for shift light kit I have (it's not a usual off the shelf one). I understand it ideally needs between 0 to 12v square wave pulse (typically the tacho feed). I've tried the two pins on the coilpack but have had no luck so far, was wondering if there is anything between the coilpack and ecu that I'm not aware of and also what the connectivity (is this a direct connection to the ECU pins?) and what the type of signalling is on those two pins. Think I read somewhere it usually +12v on these pins and it triggers on the drop to 0v. I also have to eliminate supply noise and re-check for a clean ground as well but I doubt this will be the problem causing the erratic output I'm getting. Think I'm going to have buy/borrow an oscilloscope as I'm working a little blind :-s

 

[NorthloopCup]

Hi Mark, trying to understand the right place to pick up the ignition pulses for shift light kit I have (it's not a usual off the shelf one). I understand it ideally needs between 0 to 12v square wave pulse (typically the tacho feed). I've tried the two pins on the coilpack but have had no luck so far, was wondering if there is anything between the coilpack and ecu that I'm not aware of and also what the connectivity (is this a direct connection to the ECU pins?) and what the type of signalling is on those two pins. Think I read somewhere it usually +12v on these pins and it triggers on the drop to 0v. I also have to eliminate supply noise and re-check for a clean ground as well but I doubt this will be the problem causing the erratic output I'm getting. Think I'm going to have buy/borrow an oscilloscope as I'm working a little blind :-s

No need for an oscilloscope mate. There's 3 wires going to the coil pack wiring. 2 are signal wires and the other is the feed. Very easy to distinguish the feed wire as it's the thickest one of the three and it's also plain white. The coil pack gets its 12v + when the ecu applies the earth - to the pins in the ecu plug. Pin 1 is definitely one of the wires, and I think pin 31 is the other. I'd need to double check to confirm 100% though.

So the next question for you is what shift light have you got?

Reason I ask is that you need one that will operate on 2 cylinders due to the wasted spark ignition on 1*2's. If you set it to 4 it just won't work correctly as it's not seeing the correct pulses. You could possibly tap into both of the wires and feed them both into the unit, but that would mean you'd need to incorporate diodes on each wire to stop them both energising each other when they are triggered. That's way to much faff for a shift light as far as I'm concerned!

 

[eon172]

Apologies for the late response. Thanks for the info, so those two trigger pins are direct connections to the ECU then, thanks. I understand the wasted spark setup, it was moreover to understand the direct wiring and the form of signalling which I expect is pulsing from ~+12v to 0 on each trigger given it seems to be averaging at just under +14v on those pins when running (tested only with a multimeter). Also wanted to see if there are other tacho/engine speed outputs that I could tap into, maybe the crank sensor...

Hence if yourself or anyone else has an ignition system/ecu connection circuit diagram you could share, I would be much appreciated.

The system I'm attempting to install is not a commercial off-the-shelf product, more like a DIY kit running off an Arduino nano board. The software allows for allot of control over the pulse per revolution and some signalling methods and conditioning, but I expecting the signalling on the Renault ignition system is either just too dirty or not compatible, hence I may need more tweaks to it. I've got hold of a scope now so I'll get some testing done tomorrow, plus a signal generator to test the device off of the car to rule that out.

If it's not already obvious I've gone gone down the faff route, but I do like a challenge ...If I get it working I post something on the forum, keep threatening to do a project thread one if these days. Cheers.