Hi everyone,

I’m working on a Gibidi BA24 gate controller board and need some help identifying a specific diode that seems to be causing an issue. The board controls the operation of electric gates, and I’ve come across a diode that appears to be burnt.
The diode looks burnt or damaged.
Using a multimeter, I measured the forward voltage drop of a similar non burnt diode, (attached the photo of measurement) .
I am attaching also a picture of the whole board and of the burnt diode.. I want to replace It but without a schema I am not able to find the right one to buy.. can you help me?

 

Using a multimeter, I measured the forward voltage drop of a similar non burnt diode, (attached the photo of measurement)

What voltage reading is on the suspected bad diode D7?
From the photo it looks like a common 1N4148 surface mount diode or equivalent.

 

You can't reliably measure a diode while still in circuit, as it might have other components in parallel with it, such as inductors. You have to remove the diode, or at least lift one "leg" of it. However, you can't lift a "leg" of a surface mounted one, you have to remove it to measure it....

 

If the diode reads either zero or open in both directions using the diode check function of your meter then it is suspect, and needs to be CAREFULLY removed for an additional check. Be sure to note the polarity before removing it. If it is a Zener diode it should still exhibit a forward conduction. And a caution is that most diodes of that style look a lot alike. So you really need the circuit to know what it is.

What is the symptom of the PCB that a bad part is suspected?