Sony d-808k acting weird

Kostgeor

Hello mr kaosun!
I have 2 d-808k discman and they both have the same problem. The problem is that by pressing play, the unit does not start always. Sometimes it starts playing fine, sometimes it does nothing. Tried both dc jack and batteries. If the unit starts, then everything works perfect, it can play the whole day. Checked the cpu (IC801) VDD pin and it has correct voltage, stable at 3.3v, even when the unit does not work. The units are both recapped, cleaned, and broken vias/traces have been restored. Have you ever experienced anything similar before? What can it be?
Thanks for any help or advice,
Kostgeor.

kaosun

Check the following conditions when the issue appears:
1: CPU voltage,
2: CPU reset,
3: CPU oscillator,
4: Hold switch,
5: Play button.

If all 5 conditions ready, the screen shows 00. If no mechanical movement, further check power on signal from CPU, sending to drive chip: MPC1715.