[Dead] C250i BASEB PWB Replacement

[Slammers]

I have a C250i in the field that is failing to boot past 50%.
Boot diagnostics FW JIG reported dead SPI flash on CPU-B and we ordered up a replacement CPU-B.
Issue persists after replacement.
We can load FW/Boot rom etc no problem but machine never goes past 50%.
The internal boot diagnostics (Hold Sub Power + Turn ON) suggests that the issue is related to either Program/FW, CPU-B PWB (This has been swapped) OR BASEB PWB.
I have atatched the exact step of failure from the bulletin. Device is exhibiting the Abnormal operation symptom at this step (All lights remain lit).

I have a spare BASEB-PWB in the workshop and the service manual steps for removal detail removing the TPM Chip (The standoff is one of the securing fasterners to the chassis).
When I insert this into the dead machine, what TPM chip do I use? The one from the spare board (Board Matched) or the one from the dead machines BASEB (Device Matched)?

The Service manual does not detail which TPM chip to use during the replacement process and I was wondering if anyone had any info before I perfrom the swap.
Cheers.

Also, if anyone else has had this boot issue and resolved it, please enlighten me The usual failure I get is the 25%!

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[Synthohol]

is LK-115 installed?
if not i dont think its even being used.

[Slammers]

is LK-115 installed?
if not i dont think its even being used.

Thank you for this. I should have read the section for the TPMB!

The TPM chip cannot even be initilazed unless LK-115 is installed.
The dead machine and parts machine do not have LK-115 so it looks like it won't matter what chip is used.
For my own sanity I will just keep the TPMs together with their respective BASEB and if I have any issues I will update.

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