I tried to replicate your error in my TurboTax Download CD software, but could not. I added a Schedule C and some limited partnerships, but none of the partnerships used the self-employment income or half the SE tax from the Schedule C business. But, I don't have the specifics for your partnership K-1s (or the other entries in your tax return), so I can't be sure I exactly replicated your data.
Somehow your file is "linking" your K-1 Section D2 line 5 to the Schedule C self-employment income or SE tax, but I can't find how that is happening. The Line 5d is attempting to calculate the QBI portion of the deductible SE tax, but should be zero if there is no box 14 code A amount for the partnership K-1.
I recommend that you contact Customer Support and provide them with a diagnostic file to find out more.
[Edited 7/16/2020| 10:20 am PDT]
@Zbucklyo
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