LM4 swap, no spark

Hi guys,

I'm swapping in an 04 LM4 from an Envoy into my 04 ZR2 Blazer.
Stock block, ls1 car intake, L59 injectors, and running the stock Blazer's P59 PCM with an LM7 cable throttle body and MAF.

Built the harness myself based on the stock Blazer harness, but populating the silverado wires and pins as needed.

I have segment swapped with HPTuners.

04 express van Engine and Engine diagnostics segment swapped in (for cable throttle and old style AC controls) but most parameters from the L59 dropped in over that.


So now the problem: I'm not getting any spark.

I've confirmed +12V and good ground at each coil subharness connector.
I've traced and confirmed with a multimeter each PCM pin to the connector.

VATS is removed.

hptuners is reading RPM signal when I crank, so CKP seems to be working.

Any thoughts on what to check?

Attachment 91733

Do I need to segment swap the "system" segment also?

Solved: switching the "Crank low res" to a zero from a 1 got me spark, and it started up first try.