12200411 PCM swap for 1996 to 2000 GMT400 trucks

[Douglas1300]

is there anything in the tune that needs to be changed to convert the 8 individual coils into 1 signal for the ICM? all though i'm not even getting 1 spark at the coil.

 

[AK49BWL]

There is, but it's already set correctly in your tune file... System -> General tab, Vehicle, System Options: GMT610, all the way toward the right is Crank Low Res, set to 1. That tells the PCM that you have the 4x reluctor ring as opposed to the 24x... I do remember reading a while back that in order to swap between 4x and 24x you had to write-entire a tune file FROM a vehicle that had 4x or 24x, whichever one you want to use, and it'd change the firing order of the injectors as well... The 0411 out of the Express vans shouldn't need to be modified as they had the 4x 350s, but if you got the PCM out of a newer vehicle with CoP (5.3, LS, etc), you'd need to flash a 4x tune to it. With that said, I haven't heard whether that has changed within the last 4 years since I read that

 

[Douglas1300]

do I have to change something in the tune for the 4X crank vs 24X crank signal? i'm missing something.

 

[Douglas1300]

I got it from an 05 or 06 blazer

 

[AK49BWL]

No, the reluctor signal is already set correctly in the tune file you sent me. 05 was the last year for the blazer, and they didn't come with the 0411 PCM... 2003+ had 1MB PCMs with the blue and green connectors rather than blue and red.

 

[Douglas1300]

I just tested the PCM output to the ICM with an LED set and that all looks good, so I'll grab an ICM tomorrow and I should be in business. thanks everyone for the help.

 

[Christian Steffen]

I got it. sent you the file Christian. the link for your email had .con.

Sounds like it was already looked over, if i get time i'll still look. It's been a busy couple weeks for me.

 

[Douglas1300]

its running now with a new ICM. it is rough though with a lot of misfiring.

 

[toomanyhobbies]

I am looking for the pinout sheet for an L31 for a '98 K1500. If someone can share please PM me. I have acquired the 0411 box and the plugs.

I went to the other forum and PM'ed Lextech a few days ago. Waiting to hear back.

Thanks

 

[toomanyhobbies]

Still waiting. Been 3 weeks. PM'ed a second time. Anyone know of any other way to get the pinout sheet?