What component ?

[keeney123]

Re: What component ?

As I look closer I saw a couple more. It is hard to tell by the picture. I have circled in red where I question the connection.

[keeney123]

Re: What component ?

Some photos :

You need to use a black background under the board turn the flash on the camera "off". If you take the picture outside and use natural light take the picture before 10 am or after 2 pm. If you take the picture inside do not shine light directly on board. Make the light around the board bright enough so the picture snaps quick enough so there is no blur. An make sure camera is on macro.

[keeney123]

Re: What component ?

Ok, I'll do that,
one of the TVS diode is short, showing value on both test reverse and forward...

Are you on the lowest scale on your analog meter? Around 200 ohm scale and is this reading off the board? Also, I think Stj is thinking you have a short from the power pin to ground.

Does anyone have a schematic of the board?

[bianchi77]

Re: What component ?

All the resistors are 0 ohm ....

[bianchi77]

Re: What component ?

All the resistors are 0 ohm ....

[bianchi77]

Re: What component ?

yes around 200 ohms on the lowest scale on analog meter..

[keeney123]

Re: What component ?

yes around 200 ohms on the lowest scale on analog meter..

Are you measuring the TVS off the board?

[bianchi77]

Re: What component ?

yes I measured it off board....

[keeney123]

Re: What component ?

yes I measured it off board....

So from the below post you said one of the tvs is shorted. The other is not? Do you have have the part number on the TVS? When you say shorted is that less than one ohm resistance? Have you but your leads together on the 200 ohm scale and adjusted the needle to read exactly 0 Ohms?

[bianchi77]

Re: What component ?

As I look closer I saw a couple more. It is hard to tell by the picture. I have circled in red where I question the connection.

Ok, how can I test it ? with meter from front and back ? and see if it's open ?
how to fix it ? put a solder on it ?

[bianchi77]

Re: What component ?

So from the below post you said one of the tvs is shorted. The other is not? Do you have have the part number on the TVS? When you say shorted is that less than one ohm resistance? Have you but your leads together on the 200 ohm scale and adjusted the needle to read exactly 0 Ohms?

I'll have a look and post it...

[bianchi77]

Re: What component ?

As I look closer I saw a couple more. It is hard to tell by the picture. I have circled in red where I question the connection.

is it rusted or burned ? how to fix it ? put a solder ?

[bianchi77]

Re: What component ?

some magnified photos

[bianchi77]

Re: What component ?

looks like it's a dust or rust...I clean up with alcohol...

[bianchi77]

Re: What component ?

The shorted TVS code is AE

[budm]

Re: What component ?

The circuit does not need TVS to be in the circuit for the circuit to work, it is just a protection device, so if the TVS is removed does the board function? Low resistance is still present at the two EMPTY pads of the removed TVS?

[keeney123]

Re: What component ?

looks like it's a dust or rust...I clean up with alcohol...

So they look OK. I had thought the trace was missing.That does not seem to be the case in the close-up photos. Any time you have a question in the continuity of a circuit you can just Ohm it out to make sure it is connected. I would try as Bud M suggested. Look at the Voltage lines coming into the board to see what if anything happens to them. I would just connect the power lines first and observe the voltage. If that works OK then connect every thing up. Before you connect the power lines make sure the voltage is present on the connector.