BOSS DSD-3 Problem - won't turn on in Delay mode

[ins0mniac]

Hello all,

I have an old BOSS DSD-3, after playing the other day I forgot to unplug the power source and it was connected over night. The pedal was not engaged, only plugged in. I've seen in the morning that it is still connected and tried to see if it still works but it would not come on.

The pedal has two delay modes and two sampler modes. It does work in the sampler modes as it used to.

When I try to use the delay the LED just won't come on and there is no effect. Immediately after power is applied to the pedal, I do hear the unprocessed sound trough the pedal.

When I apply power to the pedal with the mode selector on a sampler mode, the LED is lit for 5 seconds automatically and then goes dark.

I have seen a similar posting here for problems with the DD3, as far as I see the DD-3 is very similar to the DSD-3. What I did till now is to check the voltage on pin 5 of the BA634 chip, with power applied it is between 8.6V and 9V depending on which mode is selected. I also tried to see if there is a voltage on C55 but I am not sure that i measured right, the PCB is very tight and there are lots of leads so I will try to remove it from the pedal before attempting other measurements.

All tips are welcome on what to check next.

Greetings,
Insomniac