8L90 - removed tcase and made 2wd, no speed reading now

I'll try and keep this brief.

Building a desert Bronco, 2wd Ibeam truck with an L86 and 8L90. Truck has been tuned and running well until i removed the transfer case. I removed it and added the fixed yoke from a Camaro to gain much needed driveshaft length and better angles. No need for 4wd anymore anyway.
Yesterday once i added the new shaft and drove the truck but it's in limp mode and not registering speed any longer.
My tuner doesn't know what to do and i don't get why the only speed sensor would be in the tcase and not the transmission. It shifts fine, just no power any longer which seems to indicate limp mode. Only code is P17D4.

Is there a specific 2wd 8L90 TCM tune that will then pick up the transmission speed sensors?

Trans type configured?
VSS location configured?

I have an 8L90 in my '15 Yukon Denali.
ECM trans type is "Auto"
ECM Auto trans type is "C2C"
VSS/OSS Location is "after gearbox"

Aside from that, i'm sure you know there's a process to converting a 4wd trans to a 2wd trans. if you've done whats needed, then make sure the sensor is placed properly... close enough to pick up the reluctor (toothed ring) as the output shaft rotates. If its too far away, the sensor won't provide the required signal.

I got it running and moving again, turns out one of the small bearing broke and some metal was attached to the speed sensor. It shows speed now and shifts but the trans is in limp bode stil.

The trans has a speed sensor so no need for an external one, i don't think. I didn't write the tune and don't know HPT very well, i don't see these settings in the tune editor. I asked the tuner and he's researching ideas. I think there might be 2 speed sensors and at least one is working but in VCM scanner i only show one speed channel and it shows the speed when i data log. I'm stumped and it sucks

Quote:

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Originally Posted by brainofjjj

I got it running and moving again, turns out one of the small bearing broke and some metal was attached to the speed sensor. It shows speed now and shifts but the trans is in limp bode stil.

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Disable that DTC, write calibration, and try again. :shrug:

Quote:

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Originally Posted by 1badc10

Disable that DTC, write calibration, and try again. :shrug:

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How would that solve my issue? Would an error code cause it to be in limp mode?
The only code is P17D4

Quote:

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Originally Posted by brainofjjj

Would an error code cause it to be in limp mode? The only code is P17D4

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If memory serves (~15 years ago), active diagnostics would limit transmission functionality. Aside from that, have you & your tuner tried manually activating things (special functions) using diagnostics tools within VCM Scanner? There are features that would allow you to trigger/activate certain functions, with the vehicle running.

I don't want to offend you by asking how much "diagnosing" have you two done, using the available features within VCM Suite?

Quote:

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Originally Posted by 1badc10

If memory serves (~15 years ago), active diagnostics would limit transmission functionality. Aside from that, have you & your tuner tried manually activating things (special functions) using diagnostics tools within VCM Scanner? There are features that would allow you to trigger/activate certain functions, with the vehicle running.

I don't want to offend you by asking how much "diagnosing" have you two done, using the available features within VCM Suite?

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I'm going to swap out the fluid for the blue label ATF this week then try the relearn process once the fluid is hot enough. My tuner hasn't gotten back to me on his recommendation yet and i may have stumped him. This is the last piece of the swap puzzle for me and has taken me far too long to sort out. Appreciate your help so far.