Quite possibly a CD is stuck in the unit. I've tried taking out the radio fuse and then replacing it without success as per another sites suggestion. Per Lexus a $900 fix which is crazy!! Any input will be appreciated.
Bill

I had the same problem and the dealership quoted me the same amount for replacement with a refurbished unit.

I went online and found a refurbished unit off of Ebay for $200 dollars. Took me about an hour to remove the old head unit and replace it with the refurbished unit.

If I was more adventurous (and didn't find a replacement unit), I would have opened the CD changer and tried to fix the mechanisms myself.

Here is a youtube video that I found that pretty much what I did.

See post #3
https://www.clublexus.com/forums/rx-...error-4-a.html

I know this is late to the thread but I have had repetitive issues with Error 4 on my '05 Lexus RX330 CD-6 changer but have managed to work it out with a metal ruler to open and pushing a cardboard back of a notebook inside, moving it around a bit, stopping the car and restarting it.

But now it seems to be really stuck. I have cleaned the inside with alcohol prep pad, took the radio 1 fuse out twice.

Haven't tried the battery reset but my question is this. I called one audio shop and they said they can only remove the cd by taking out the unit and if they take out the unit and put it back, it won't work anymore. ?

Does it make more sense to send the unit for repair (therefore no code issues to deal with), or buy a used/refurbished?

Thanks