13" G07 F901 blows. Not usual suspects.

Mitsurugi-w

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I bought a Centipede cocktail table for cheap off CL. The monitor didn't work and when I took it out I noticed the F901 fuse was blown. I looked at the flow chart and it said to check the HOT and the Flyback. Flyback looked fine so I replaced the HOT and the fuse. Powered up and the fuse blew immediately. So for the hell of it I changed the flyback and the fuse again. Powered up and the fuse blew immediately.

What should I look for next? I guess this wont be as easy as I thought....
 
If it was an original flyback, it was probably bad which took out the horizontal output transistor.

Remember also that the horizontal output transistor as well as the B+ regulator transistor both need to have a mica insulator.
 
Yeah I replaced the flyback and HOT at the same time. I need to check continuity between the HOT, regulator and chassis to make sure there is none. I did use the insulator when I changed the HOT.

What would the yoke resistance be if its bad? I couldn't check the IC with a DMM could I?
 
Yeah I replaced the flyback and HOT at the same time. I need to check continuity between the HOT, regulator and chassis to make sure there is none. I did use the insulator when I changed the HOT.

What would the yoke resistance be if its bad? I couldn't check the IC with a DMM could I?


Check your bridge rectifiers, if one of them is shorted inside it'll dump everything to ground and keep blowing the fuse.
 
When I test for continuity while the Hot is attached to the chassis but the wires are disconnected there is no continuity between the hot and chassis. When I hook up the wires there is then continuity between the chassis and the hot. Is this normal or could it indicate a shorted bridge rectifier?
 
I was able to solve this problem. It turns out that the legs of FR401 and R415 shorted against each other and caused both to fail. After I replaced them, the fuse and the HOT that had fried again, it fired right up.

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