highlighting active cells used in formulas across different worksheets/tabs

Scott-

This is actually a pretty complicated issue.  I have attached the below VBA Code as well as a sample workbook that you can use to see how it works.  I have modified Bill Manville's find precedent code in order to do what you require by adding in a few snippets to color the precedent cells yellow.

This is his webpage:

http://www.manville.org.uk/

In this example you must select your cell and then run the macro.  I have used Sheet1!C4 as the cell to select in this example.

The Precedents are:

Sheet3!F7

Sheet3!F12

Sheet4!F5

K11

Sub FindPrecedents()
    ' written by Bill Manville
    ' With edits from PaulS
    ' this procedure finds the cells which are the direct precedents of the active cell
    Dim rLast As Range, iLinkNum As Integer, iArrowNum As Integer
    Dim stMsg As String
    Dim bNewArrow As Boolean
    Dim myrng As Range
    
    Application.ScreenUpdating = False
    ActiveCell.ShowPrecedents
    Set rLast = ActiveCell
    iArrowNum = 1
    iLinkNum = 1
    bNewArrow = True
    
    Do
        Do
            Application.Goto rLast
            On Error Resume Next
            ActiveCell.NavigateArrow TowardPrecedent:=True, ArrowNumber:=iArrowNum, LinkNumber:=iLinkNum
            If Err.Number > 0 Then Exit Do
                On Error GoTo 0
                If rLast.Address(external:=True) = ActiveCell.Address(external:=True) Then Exit Do
                bNewArrow = False
                If rLast.Worksheet.Parent.Name = ActiveCell.Worksheet.Parent.Name Then
                    If rLast.Worksheet.Name = ActiveCell.Parent.Name Then
                        ' local
                        stMsg = stMsg & vbNewLine & Selection.Address
                        
                        
                        'This colors the local Precendent Yellow
                        '======================================================================
                        Selection.Interior.Color = vbYellow
                        '======================================================================
                        
                    Else
                        stMsg = stMsg & vbNewLine & "'" & Selection.Parent.Name & "'!" & Selection.Address
                        
                        
                        'This colors the Precendent on a different worksheet Yellow
                        '======================================================================
                        Sheets(Selection.Parent.Name).Range(Selection.Address).Interior.Color = vbYellow
                        '======================================================================
                        
                        
                    End If
'                Else
'                ' external
'                stMsg = stMsg & vbNewLine & Selection.Address(external:=True)
                  
                End If
                iLinkNum = iLinkNum + 1 ' try another link
        Loop
            If bNewArrow Then Exit Do
            iLinkNum = 1
            bNewArrow = True
            iArrowNum = iArrowNum + 1 'try another arrow
    Loop
    rLast.Parent.ClearArrows
    Application.Goto rLast
    MsgBox "Precedents are" & stMsg
    Exit Sub
End Sub

In order to use the code you will need to:

1. Download the sample workbook

2. Select Cell C4 on Sheet1

3. Use key combination Alt + F11 to access the Visual Basic Editor (VBE)

4. Insert > Module

5. Paste this code to the new code module

6. Run the code by clicking the "run" button in the VBE (The little green triangle that looks like a play button)

Hope this helps!