1. Click the Select object pointer. Use Shift-select to select both car graphics and also Shift-select the thick black diamond lines.
2. Click Properties Editor (the pencil and paper icon) to open the Properties Editor. Clear the Overprint check box and click Apply.
3. Clear the selections of all objects. Click Highlight objects set to overprint to confirm overprints have been taken off.
4. Click the Trap Page icon on the top toolbar . In the Trap Page dialog box, click Trap Page.
5. Click Highlight traps to display traps and check that cars and lines are properly trapped.
6. Use the Acrobat output preview tool (Tools > Print Production > Output Preview) to confirm that the file is trapped correctly.
7. Close and save the PDF file.