Several vintage radios use soldered tags or diodes on the circuit board to set the security code, rather than have the code in a 'chip'. Known as hard-wired or 'hard-coded' models, in most cases these codes need to be reset.
Our service is no longer offered, due to retirement of the business owner. However, a very good alternative still exists and we recommend you contact Peter Smith at Restored Classic: restoredclassic[at]aol.com
I highly recommend Kevin and his team. They helped me “break the code” on my 1980’s vintage Blaupunkt Boston SQR49 car radio. Their directions were clear and the pictures they supplied made the process very easy. Plus they were there to coach me through the process. Thanks guys! Tony C. – USA.
Thank you a lot for swift reply and, what's more important, the right answer. The radio works again. Jiri - Alpine CM5905, BMW E24 635Csi
Bit of a challenge with a wood burner and exacto knife, and my bumbling soldering skills, but got it done and the radio works perfectly. John - 1995 BMW 540i, Alpine CM5903L
Kevin, that worked like a champ! Thanks again! Mike Wagner - Boston SQR49
Tried to fix the radio today... it totally worked! This is awesome! Thanks so much! Jim Paris - Blaupunkt Malibu CR42
It worked! Thank you so much! Michael Montijo - Alpine CM5907 in 1987 BMW 325e
The code is often set according to which of several pairs of solder tags are bridged. In most (but not all) cases, any database of the codes that may have existed is long gone. Information provided (contact Restored Classic) will allow you to reconfigure the tags to set a new code. This will require input from your side, at the very least to take a photo of the circuit board. In most cases someone will need to be able to use a soldering iron.
You need to pull the radio from the dash to read the model number and to remove the lid of the casing to check the current tags or diodes configuration. Wait until after you have been sent information; you will be sent photos of the PCB to help you find the tags section.
Some of these radios can be fiddly to remove, requiring that you first remove one or more trim-plates or small plastic panels to reveal screws that need to be released, but others will simply need extraction keys inserted into the visible holes/slots in the front facia.
PLEASE NOTE: If you are not comfortable opening up the unit and using a soldering iron, we strongly recommend that you take the unit to a car radio service agent to avoid damaging the circuit board.
We no longer offer to decode these radios
As an alternative service we recommend Restored Classic: restoredclassic[at]aol.com