Behringer Eurolive B212A - Dead

[misterc57]

I picked up a B212A that I knew was not working. There was no fuse holder cap or mains fuse. I borrowed one from a B215A to test it out.

I suspected it was blowing fuses since the fuse cap was missing. I plugged into a light bulb current limiter with a 40 watt bulb. The bulb lit brightly.

My first suspicion was the power transformer. I unplugged the PT secondaries from the unit circuit board and plugged back into my current limiter. This time the bulb did not light.

The secondary wiring colors are two yellow, two orange, and one brownish center tap. I am getting 56.9 VAC across the two yellow wires, 121 VAC across the two orange wires.

At this point I believe the PT is good. Since the light bulb on the limiter is coming on, would this indicate a short on the main board? I am wondering where to look next.

I have attached the schematic.

Much thanks for your help!

MC

[Enzo]

Transformers should be the last thing on the list, not the first.

BLows fuses? First thing to check is for shorted output transistos. Also look for shorted rectifiers;.

[misterc57]

Transformers should be the last thing on the list, not the first.

BLows fuses? First thing to check is for shorted output transistos. Also look for shorted rectifiers;.

What is the procedure for checking each for a short? Can those be tested in cicruit?

Thank you!

[diydidi]

Check fuses F1 and F2. Sometimes if one is open, it can cause bulb limiter to light.

[misterc57]

Check fuses F1 and F2. Sometimes if one is open, it can cause bulb limiter to light.

Fuses are ok.

[misterc57]

Problem fixed. Open Diodes D20 & D21.

[Soovls]

I picked up a B212A that I knew was not working. There was no fuse holder cap or mains fuse. I borrowed one from a B215A to test it out.

I suspected it was blowing fuses since the fuse cap was missing. I plugged into a light bulb current limiter with a 40 watt bulb. The bulb lit brightly.

My first suspicion was the power transformer. I unplugged the PT secondaries from the unit circuit board and plugged back into my current limiter. This time the bulb did not light.

The secondary wiring colors are two yellow, two orange, and one brownish center tap. I am getting 56.9 VAC across the two yellow wires, 121 VAC across the two orange wires.

At this point I believe the PT is good. Since the light bulb on the limiter is coming on, would this indicate a short on the main board? I am wondering where to look next.

I have attached the schematic.

Much thanks for your help!

MC

i think, i have a same problem like as you.
Please, can you send me that wiring-diagram?
I can not download it from yours link.

ALL Best!

[Jazz P Bass]

The schematic can be found here.

BEHRINGER B212A SCH Service Manual free download, schematics, eeprom, repair info for electronics

[Jazz P Bass]

Reload of schematic: behringer_b212a.zip