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The Palmer is Palmer Power Supply PW12MKII Power Box Brand new. 2 months old
From Boss I have an 20 30 years old 9v adapter that have served me fine for many years, I never use it for other than testing.

laurie wrote: ↑

Sun Feb 12, 2023 8:07 pm

No issues with solder joints.

Well, it could be that the solder joints of the wires coming from the LED don't have a proper connection to the circuit board anymore. If Tnsen put the tips of the multimeter on the solder joints, it doesn't say too much about the further circuit path. I would double-check if there is a proper connection between the wires directly at the LED and the next components in the circuit path after the wires.

I have seen cold solder joints of wires in BOSS pedals before.

Pepe wrote: ↑

Sun Feb 12, 2023 8:35 pm

laurie wrote: ↑

Sun Feb 12, 2023 8:07 pm

No issues with solder joints.

If Tnsen put the tips of the multimeter on the solder joints, it doesn't say too much about the further circuit path.

Ah yes, but I read that the test was done from point 13 and point 15 on the main board... ?

Pepe
I can try it to morrow. It`s late here in Norway and i have put away the tools for today.
I`m on a MIDI mission to, have started to learn about it to. Just bought me SY1-200 and 300 and want to set it up with my FC-300. It`s a process when I`m over 50y old.

T

laurie wrote: ↑

Sun Feb 12, 2023 8:44 pm

Ah yes, but I read that the test was done from point 13 and point 15 on the main board... ?

Yes, that may be, but that still doesn't say anything about the connection to the circuit board. With the continuity check/diode test function of a multimeter the LED will also light up if this end of those two wires aren't connected to the board at all.

Pepe.
I`m not an expert, but how can that be? There are 2 wires, Green goes to 13 and Orange goes to 15. If you have a light bowl with to wires and take the wires away from a battery then the led will not light up in my head, but i`m not an expert. Will it not be the same here in my CE-2?

T

Didn't you say that you only checked the LED and the wires with your multimeter? Did you leave a battery or power supply connected to the pedal?

If you check a completely disconnected LED with a multimeter, it will light up if you touch the correct legs.

I did not have a battery or power in my pedal. Only the multimeter.

You did say, the LED will also light up if this end of those two wires aren't connected to the board at all. This is something I not completely understand.
Not to argue or be stupid. I`m just trying to learn.
I`m not trying to trolling here, but I have learn that If you have a led you have to have let's say 2 wires. and if one is taken away or if there is a break in it then there will be no light
Since I'm not an expert, can such a circuit board make it so that it will be like you say?

Hey, Tnsen, I know that you aren't trying to troll us! Only a few years ago I have been at the same point of having not a clue at all how to proceed with the repair of a pedal (or a synthesizer).

Here is an illustration how an LED can be tested with nothing more than a multimeter:
If the LED lights up when you check the pins 13 and 15 we only know that the wires that you touch are properly connected to the LED.

If the LED lights up when you check the same at the next components in the circuit board then we know that the wires are also properly connected to the circuit board. So please check the following points with the multimeter:
If the LED doesn't light up now, the wires 13 and 15 only need new solder.

@laurie: before the LED and the resistor R51 there is a zener diode D6. Let's assume that this one could be the culprit - would the rest of the pedal work normally like Tnsen describes it?

Hi Pepe
Have tested now. The light came on when I did as you told me to do. Thanks for the learning. appreciate it.
Found a place where i could turn the knob and the meter did go up and down, awesome. learning, learning learning.

T