Navigation system is blank

Hello, no real recommendations here, except you may want to look more into what sends the signal to the display -- compared with what you actually replaced. Sounds to me that the part you replaced was not the root of the problem, so maybe that will help additional troubleshooting. These are largely obsolete systems after 20+ years, so I'm not sure how beneficial this repair is anyway. Use this link to find some shops near you that can help with your concern: www.repairpal.com/repair-shops