Theta Data Basic disk detection problem.

Hi all!

Please help me to identify the problem with my CD transport based on CDM9 Pro.
The bottom line is that recently my CD transport stopped reading discs, when I insert a disc, the motor spins up, no errors are written on the screen, while the swing arm slowly moves from the center to the edge of the disc and as soon as the laser head reaches the end of the edge , the disk starts to rotate in the opposite direction, while there are no errors on the screen.
The CDM9 block itself is working, since I move it to another of my same CD transport and it works without problems there, the same thing is proved by the fact that if I rearrange the entire CDM9 block from a normally functioning CD transport to this non-working transport, then the reaction is the same, i.e. the swing arm moves slowly from the center to the edge of the disc. It turns out that the problem is in the main board of the CD transport, but in which direction to look? Also, if you start the self-test with the STOP + << TRACK >> + POWER buttons, the focus test passes, the swing arm moves, the disk spins up, but when you exit the self-test with the PLAY button, ERROR 34 is briefly displayed on the screen. Unfortunately, I did not find a description of this error. Version of the microcontroller program on the screen when starting the self-test P133. The connecting cable between the CDM9 block and the main board was also changed to a known good one. The voltage after the voltage regulators is also normal.

Please help me identify the problem?

Thank you for your attention.
 
Last edited:
Sorry, I didn't understand your question. What did I do to find the problem? So I just can’t understand in which direction to look, or rather, I want to understand what problem usually causes the smooth movement of the swing arm from the center to the edge, while no error appears, but the TOC is not readable either.
 
I found a service manual from a similar player on cdm9, and there is a description of the error codes. If my vehicle correctly detects error number 34 upon exiting self-test, then judging by the description, this is "xx= 34 : search time error". But what does this mean?

ERROR MESSAGES
display : A5 xx0000
xx= 2 : focus error
xx= 3 : radial error
xx= 5 : off error (TL stays low for 5 1
msec.)
xx= 6 : jump error
xx= 7 : subcode error, no valid
subcode in 3 sec.
xx= 8 : TOC error : out of lead-in
area while reading the TOC
xx= 30 : too many grooves to jump
xx= 31 : search time out
xx= 32 : bin. search error
xx= 33 : search index error
xx= 34 : search time error
xx= 37 : selection error
 
it must be something like this
1658813098876.png