Chevy Aveo T250 ECU pinout

[Ajax]

Hi! So, I was studying the pinout of my ECM, and it looks something like this:
pinout 1.png
pinout 2.png
As you can see, there are two similar set of pins. One set controls ignition for coils 2 and 3 and the other for coils 1 and 4.

I have a single coil system, so I assume those pins control the spark plugs directly by sending a signal to the coil.

My question is, why are there two sets of pins that control the same instead of 4 pins (one for each spark plug)?

Are two spark plugs firing at the same time? Do those pins only control timing, and the firing is directed by a different circuit?

Thanks in advance for any help you can provide.

[gtstorey]

Have you checked the wiring diagram? It will tell you more than the pin out.

[gokart2]

From back in the day old Ford stuff, single coil 4 cylinder 2 plugs always fired the same time. Was supposed to help with emissions iirc. One was always compression cycle while the other was always exhaust cycle. It's been awhile but that's how I remember it.

[Robergts]

https://www.youtube.com/watch?app=desktop&v=EJpphi-CDw4

[Ajax]

Have you checked the wiring diagram? It will tell you more than the pin out.

I'm not sure where to find that, there is tons of crappy info out there.

From back in the day old Ford stuff, single coil 4 cylinder 2 plugs always fired the same time. Was supposed to help with emissions iirc. One was always compression cycle while the other was always exhaust cycle. It's been awhile but that's how I remember it.

Hm, that makes sense. Tahnk you.

https://www.youtube.com/watch?app=desktop&v=EJpphi-CDw4

Wow that's very useful, thank you!

[gtstorey]

alldata.com or https://www.acdelcotds.com/subscriptions# or buy a hard copy OEM service manual.