I had the same trouble with my first BMW. If you can't find anything about it in your manual, take it to an official dealer or tech center. They'll have that unlocked in no time. The alternative is just getting a new head unit.

Here are FREE and EASY instructions to get your Honda radio UNLOCK CODE from my experience. (Dealerships usually charge) Assuming you don't have the Anti-Theft Code and Serial Number that is found on the credit card sized Anti-Theft Radio Identification Card that comes with the vehicle at the time of purchase and is usually found in the glove compartment.... You have FREE options to retrieve that code by phone or on the internet BUT, the RADIO SERIAL NUMBER is REQUIRED (no matter what). (see bottom about removing ERROR E3) ***IF your Honda was made BEFORE 2001 the serial number MAY not be accessible without removing the radio from the vehicle.*** * TO GET THE SERIAL NUMBER (so that you can get the unlock code) 1. Get something to write with and on (you'll need it to write down the serial number) 2. Put the ingnition key in and turn it until your able to turn your radio on (accessories position). 3. Then turn your radio OFF by it's knob/button (but leave the ingition key in place). 4. Hold down the preset buttons 1 and 6 at the same time. 5. Turn the radio on while pressing down both the 1 and 6 buttons.(***IF your Honda doesn't have preset buttons on the radio then hold down the top part of the 'Seek/Skip' button AND the top part of the 'Change Disk' button instead.*** ) 6. Write down the 4 numbers you see first and then 4 more that display. These eight numbers are the SERIAL NUMBER. This is NOT your CODE. 7. Make sure your VIN (Vehicle Identification Number) is handy to get the unlock code. (can be found on your insurance card, driver's side door jam, small plate on dashboard by registration and inspection stickers, etc) * TO GET THE UNLOCK CODE (using the radio Serial Number and VIN) ---Internet option: 1. Go to https://radio-navicode.honda.com/ (YES, it's run BY HONDA and IT'S FREE) 2. Follow on screen instructions (Serial Number and VIN required) 3. Type in the 5 digit code into your radio. This will unlock the radio and return it to a functional state. -OR- ---Telephone option: 1. Call American Honda Customer Relations (800) 999-1009 2. When the automated message starts 'Press 3' for 'Radio and Navigation Codes'. 3. Tell the Customer Service Agent you need your radio code. (They will ask for your name, your radio's serial number, VIN, etc) 4. When they give you your radio unlock code--WRITE IT DOWN and KEEP IT SAFE! 5. Type in the 5 digit code into your radio. This will unlock the radio and return it to a functional state. **(alternative input method for some radios - Twist the knob and you'll see numbers move from 0-9.... twist the knob to the number you need, press the knob in and then it will move to the next digit.... do this to put in the code for the radio. * REMOVING ERROR E3 ****If you entered too many wrong codes and got an ERROR E3 message displaying you'll need to do an additional step for even the correct unlock code to work.**** Disconnect your negative battery terminal (or pull the radio fuse out if that's easier for you) for 30 seconds then reconnect it and then the radio will say "CODE" again and you can put in your correct unlock code. ----------------------------------------------------------------------------------- So what happened to begin with? See also: http://automobiles.honda.com/information/frequently-asked-questions.aspx?Question=2 If the power from your battery to the Honda radio is interrupted the Anti-Theft feature kicks in, the radio is rendered inoperable and the screen reads 'CODE'. You must enter in the Anti-Theft Radio Unlock Code (usually 5 digits) to make it operational again. You know that much by now.

I've checked https://www.radiocodeking.co.uk/honda-radio-codes/ and they are offering codes for free right now by entering this coupon code:freehondacode upon checkout. Definitely worth a try.!

check with the Honda dealership

call the Honda dealer for the code