Security code: Many factory-installed car radios have a security code that must be entered to unlock the device after the battery has been disconnected or replaced. Refer to your vehicle's owner's manual for the security code and instructions for entering it.
Fuse: A blown fuse can also cause the radio to lose power. Check the fuses related to the radio in your Corsa's fuse box. If a fuse is blown, replace it with one of the same amperage rating.
Wiring: Double-check that all the wiring connections to the radio are secure and properly connected. Disconnect and reconnect the radio's wiring harness to ensure good contact.
Software issue: In rare cases, disconnecting the battery may cause a software glitch that prevents the radio from functioning correctly. Try disconnecting the battery again, waiting a few minutes, and then reconnecting it to see if this resolves the issue.
If you have followed these steps and the radio still doesn't turn on, it may be necessary to consult with a qualified auto electrician for further assistance. They can diagnose the root cause of the problem and recommend appropriate solutions.
