Schedule K-1 Box 20 Code Z is used for Section 199A QBI entries. When entering your K-1, check that it has Box 20 and choose Code Z. You don't need to enter any amount for Code Z.
Schedule K-1 Box 20 Code AJ (any number of lines) is relevant only if your net losses from all businesses are more than $305,000 ($610,000 if filing a joint return). If this doesn't apply to you, leave Box 20 Code AJ blank (or do not include this code).
If the excess business loss does apply to you, this information will allow you to figure any excess business loss limitation that may apply. See IRS Instructions for Form 461 - Limitations on Business Losses. TurboTax does not include Form 461, which must be attached to your tax return (print and mail).
If you wish to record the amounts on your return for completeness, you will need to use TurboTax for Desktop and: