Radio/Tape problems Error Message

Does anyone know the error codes for a 98 Riviera Radio. A friend of mine has one and he can't get the tape out of the unit. When he pushes EJECT it starts clicking and then displays an "E 13"? The owners manual does not list an E 13. Can anyone help with this? I'm new to this forum and any help would be appreciated. Thanks.
greg

I know this thread is a bit old,but here is the answer.It really dosent answer your question on how to remove the tape.

~Larry~

E13 Tape communication Error Cause: The micro-processor is reading the speed pulses from the tape deck either too fast or too slow,Correction: If the tape player is still playing a cassette, try a new cassette, if there is still an error, send to service shop.