Schedule K-1, Box 20 AJ shows the following: Aggregate Business Activity Gross Income $7982 Aggregate Business Activity Total Deductions $19018 What value do I enter?

You can add the two numbers together and enter the total.

 

However, this information is relevant only if your net losses from all businesses are more than $289,000 ($578,000 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: 

1. Enter the total of all lines Code AJ in the amount for this code.
2. Go to Forms Mode, open K-1 Partner for this investment, and click the QuickZoom under Line 20 for "codes E, T, AS, and ZZ." 
3. Enter all lines for Code AJ under Code ZZ in the yellow lines/boxes. The total here must match the amount previously entered for Code AJ. This information does not affect your tax return. 

Assume the the taxpayer's total losses exceed the excess business loss threshold then what line on the form 461 should I expect to to see the Code AJ amounts?

My suggestion would be to use the numbers that are outlined by Form 461, Part I, for the calculation of the business loss excess. That Part does not ask for code AJ numbers, but rather information that is reported on your Schedule 1. 

 

Start with Schedule 1, and see what you have on lines 4 and 5 (the most common lines related to Schedule K-1 activity, but other lines may apply if you have a Schedule C, for example). The information from these lines will need to be entered in Part I of Form 461. You will then use Parts II and III to calculate the limitation. 

If you have a negative number on line 16 of Form 461, that will indicate your limitation, and that's what needs to be entered as a positive number on Schedule 1, line 8p.