E86a vs E86b differences

[LXLAW]

How do I tell which is which.

Also what part number do I look at? The one up top by the e86? Or one at bottom that says service number?

[Omega_5]

The service number is the one you want to look for. It's on the lower left of the sticker on the back.
E86A controller will be 12618516, 1268344, or 12654088.
E86B will be 12658036.

[LXLAW]

The one I have says E86 12660134 at top, service number looks like 12662677 and ABXR top right corner. Would they have put a 12654088 in a 16 model? He bought a used ecm from someone and said it was from a 16, but it’s a 4088

[Omega_5]

I don't recall ever seeing one with that service number. But, 12662677 does seem to check out as a 2016 ECM.
12654088 would not be for a 2016. If I recall, that one used in the later part of 2013/2014.

[LXLAW]

Odd… it came out of a 2016 wrecked truck. I flashed it with SPS and got it running. Ty for your help.