Radio Code Input/Reset Issue [1993 535i]

[CaptainKris]

Hi guys,

I know this has been asked a thousand times before, but I can't quite find the right answer. I'm having an issue with inputting the antitheft radio code into my stock 535i radio. The display reads 'CODE', but pressing the preset buttons that correspond with my radio code doesn't do anything. The display doesn't change or even seem like it's receiving the input, and it doesn't beep to indicate an incorrect code either. Just stays on 'CODE'. I'm assuming this means it's been locked out due to incorrect entries that the previous owner made. In an effort to reset it, I've tried completely removing the radio (both antennas and the wiring harness) then re-inserting after an hour but that didn't work. I've also tried disconnecting the battery for hour and reconnecting, but the problem persists. I've read that leaving the keys in position 2 with the radio on for an hour sometimes works, but I don't really have a safe space to do this and I can't afford to risk draining the battery like that either. Are there any other options for resetting this thing that I can try? Cheers.

[jmile46]

I did the keys in ignition 2 thing, didn’t work when I had your same issue on my 88 735. Radios probably fried.

[CaptainKris]

Ah that's annoying. I was considering replacing the head unit anyway, but I ideally wanted to keep as much stock as possible.

[ross1]

You might have a button or two that is not working. I had this once and it was impossible to input the code as one the required buttons didn't work.
Stand operating procedure is to leave the ign on for a while(30 mins?) and try the code again. A beep means you F'ed up, so turn OFF the ign and start over.
Did you get the code from the owner's book or from the radio's serial number? If the former perhaps the radio was changed, not hard to imagine after 20 something years.
Good luck.

[CaptainKris]

I'm starting to think that may be the issue. Nothing on the display changes when I press the buttons, and it still just says 'CODE'. I believe if it's been locked out it says 'CODE WAIT' and there's a beep after getting the sequence incorrect, but neither of those things have happened for me. The code was written on the radio itself.