I recently aquired some LS1 truck coil packs. I will be using these in a coil-per-cylinder application that is not on an LS1. I was wondering if anyone on here knows what each pin on the coil pack is. On the connectors it says A, B, C, and D. A and B are black and brown respectively, on all the coil packs. D is pink on all, and C changes colors for the different connector. So what do A, B, C, and D hook up to?
Thanks a ton that is exactly what I needed! So I need to wire up A, C, and D. What is Reference Low (B)? Something for the tach? I'm guessing I won't need it but wouldn't hurt to know! Thanks again crewchef!
I originally intended to use the LS1 coils with my ecu when I did my conversion.
factory LS1 coils do not operate in the normal way. ie +12v with a-ve trigger.
They appear to have +12v, -ve, ref low, and the 4th wire is a +5v trigger from the ecu, which actualy fires the coil.
Its the ref low and +5v that trigger them.
Someone did describe to me how to wire it up, using pull-up resistors that it might work via a normal trigger.
I didnt bother and just used some different coils instead, that used a normal trigger method.
I think the extra wiring is something to do with the factroy cars missfire detection ability.
However, if you do figure out how to get them to fire using a conventional trigger, please let me know.
Thanks for the information. I think if I can't get the built in ignitors working then I can still use a Bosch ignition module to fire the coil. I'll post an update in a couple weeks. The coils will be controlled by MegaSquirt n Spark Extra if that makes any difference.
u cant use an external module with these coils..
im in the process of using these coils on a 4cyl DOHC
i havent actually got it fully up and running
but i havent even got the pin for that reference ground or whatever in the plug..
how crucial is that secondary ground to the running of the coilpacks? ive heard mixed opinions, some people say dont worry about it, some say ground it to the cyl head and some say just ground it..
also does anyone have a spare ls1 coil plug with 4 wires still intact?
You want the "reference low" to be grounded to your Megasquirt grounds - PM me if you have questions, this will work just fine. You want to set up your MS with 5v triggers, so basically set up four spark outputs and copy what the Neon guys do (convert the outer LEDs to spark outs).
Ok, another question. Do I need to enable dwell control in MSnS-E, or do the coil packs also handle that independently?
And when you say I need to set up MS with 5v triggers, is there actually a configuration for that, or are the LED outputs already +5v?
Sorry for the delayed reply, I was at the Top Speed Challenge waching INTMD8SS go 200mph in his stock looking Camaro
Yes, you'll need MSnS-E dwell control enabled. You will need to find the "correct" dwell settings (not too hard to do).
The LED outputs need a 5v pullup to the negative leg, your spark output comes from that negative leg then. What you see on an o-scope is a 5v charge pulse, and return to 0 volts to fire the coil. You are planning on running wasted spark, yes? thus you need 4 spark outputs, I believe that means the 3 LEDs and the FIDLE output. Double check on making the FIDLE (or fourth spark out) into a 5v pulse same as the LEDs (this should be found on the msefi forums).
The Supra guys have lots of info on the AEMpower.com forums about the LS1 coilpacks also.
Thanks! So for the "correct" dwell settings, this should be something I can find on the internet, or do I actually have to find these out on my own by testing?
Also, this will be for a 4-cylinder Volvo engine, so I'll only be using LED17 and LED19 as spark outputs (wasted spark).
For the 5v pullup to the negative leg of the diode, does that just mean run 5v to it from somewhere on the MS board?
Thanks, I'll check out the aempower website.
Ok so you are saying the pullup is so the coil packs see constant 5v, but when MSnS-E tells it to fire, it provides the positive side of the diode with 5v, and then the voltage going to the coil goes to 0, and it fires?
I was just playing around with one of my coils yesterday with a battery, hooked up black and brown to negative terminal, pink to positive terminal, had spark wire laying next to negative terminal, and when I tapped the trigger wire to positive, it produced a spark. So if I held the trigger wire to the positive side of the battery, and then released, it would fire only then?
Ok so I finally got it running today after getting hung up on a few problems. Biggest problem was that my flywheel was a 44-2-2 wheel, even though Volvo never made manual transmission cars with this ignition system. So the flywheel is uber rare and I get to sell it.. So I got the correct 60-2 wheel on and fired it up today.
Problem: When turning on MegaSquirt, all the coils fire as they all receive constant +5v. I haven't really messed with it too much, but I have considered changing the spark output from inverted, and seeing if sending a +5v pulse would fire the coils because it obviously does to begin with, even though it is supposed to be fired when it "goes low."