How do you unlock 4 error on peugeot car radio?

To unlock a Peugeot car radio displaying a "4 Error" message, you'll typically need to enter the correct unlock code. This code is usually found in the vehicle’s user manual or can be obtained from a Peugeot dealership by providing your vehicle’s VIN and proof of ownership. If you have entered the wrong code multiple times, the radio may become locked for a period, so patience is necessary. After obtaining the correct code, follow the radio's prompts to input it and regain access.