OK let's try again: 2006 Hyundai Getz; MP3-03 radio/cd. After battery interruption, the LCD is blank.

Question edited for clarity and full 'year make model'.
Question moved to correct category.

Did you disconnect the battery when you did that work. That would mean the security needs to be reset. They seem to have a history of not starting though!!

https://www.google.com/search?q=2006+hyundai+getz+immobilizer+reset

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Best place would be from hyundai!

With all respect, my Hyundai has a similar problem and it appears to be an over-voltage problem. If you can access wiring diagrams, do so and verify all is OK. Particular attention to the quality of earthing is reccomended, as this can cause voltage issues.

Original owner may have changed the factory code. Try having dealer pull the code takes about two minutes not sure if new code will come up or just factory code. Worth a try most times no charge from dealer

see the diagram attached, and fix it. God bless you

i want buy cataytic converter used how much

try another hyundai dealer in your area. Someone should have it on record somewhere. Tell them to stop being lazy..

See if you can find the original documentation that came with the vehicle - especially anything that would have been provided when the vehicle was originally purchased. If you cannot find these documents you will need to contact Hyundai. What you will be looking for is a code to enter for the radio - the code is an anti-theft device / deterrent so proof of ownership of the radio may need to be provided in the form of the seial number of the radio.

I believe you have to call the dealership with the code and they will tell you what to enter