Martin Logan Subwoofer 2004

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jakie

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Hello Everyone!!

I need some help with my Martin Logan Subwoofer. It is from 2004 and it has been working very well until now. It keeps blowing the fuse. I tried 3 brand new fuses and it blew all. Just turning it on nothing else is connected. I took a look inside on the amp board and saw the green transistor cracked. Anyone has this problem with this subwoofer? Will replacing the green transistor fix the issue or have to replace the whole power board?

Thank you for any help with this.
 

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That 'transistor' has a "R400" board designation, so it's probably not a transistor. "R" typically represents a resistor, but that's a weird looking resistor. It could be a thermistor, which acts as a self resetting circuit breaker. Try getting a look at the other side, for a part number or value. That might help identify the part.

Also, you could check with Ron in the service center. Maybe the amp board is still available?

[email protected]

Good luck.
 
Thank you StimpyWan for your reply! You're right it's not a transistor. It is a thermistor. SCK104 is the part number. I wonder if replacing that part will fix the issue? Anyone have tried?
 
I do know thermistor's can wear out over time and fail. Replacing it can't hurt anything. That's the next logical step.
 
Has anyone tried replacing SCK104 thermistor? Both my sub blew with the same thermistor burnt.
 
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