Hi, I'm trying to enter the code for my E36 Alpine CM5903L. I believe I have the right code - both written on top of the unit and I used an online code service which gave the same number. However, on entering the code it does nothing, CODE remains displayed. I've tried leaving the ignition on for 2 hrs, both radio on, and off to clear the lock out, but still does not work. Is there another key I press after the code maybe?
I believe that just entering the five correct code digits should be enough to get it working.
It should give a "beep" sound after the fifth digit being entered indicating the correct code.
This CM5903L radio is an old unit that uses a solder tag system inside the radio for its code.
If this radio has worked OK before in your car then it could now be faulty.
If you are trying to fit it into a new vehicle then it may be locked before you bought it.
You could try removing it from the car, connect it to a battery on your workbench and leave it SWITCHED ON ..WITHOUT INTERRUPTION for several hours ( overnight preferred)to see if that resets it.