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Old 08-15-2016, 02:23 PM   #1
49studebaker
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Default KB925QF replacment

I accidentally plugged the connector from "Camera Conn" JP3 header on page 42 into "Inverter Conn" JP37 header on page 18. When I turn on my laptop, the fan spins up, the front panel lights turn on, but my laptop does not boot. I probably fried the KB925QF on page 34, correct? Is the KB925QF a chip that the laptop manufacturer custom programs? There are some KB925QF chips on Ebay. Could I have damaged other other components (resistors, diode, inductors, caps) on page 18?

https://drive.google.com/file/d/0BxO...ew?usp=sharing

Last edited by 49studebaker; 08-15-2016 at 02:24 PM..
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Old 08-15-2016, 09:37 PM   #2
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Default Re: KB925QF replacment

Do you get backlights on the screen to see anything on the screen?
What does it do if the camera not connected to JP3?
If you look at the power pins and the GND pins are setup for the JP3 header and the JP37 header, I would think the camera circuit may be damaged, and switched MOSFET for +INV POWER may be damaged.
The inverter is probably OK and not damaged when plugged into wrong connector JP3 but the power +5V line on pin 1 of the JP3 may have been grounded out.
You need to check the power pins of both headers. Things get damaged when power and GND pins are connected wrong to the loads.
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Last edited by budm; 08-15-2016 at 09:39 PM..
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Old 09-20-2016, 11:41 PM   #3
49studebaker
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Default Re: KB925QF replacment

Quote:
Originally Posted by budm View Post
Do you get backlights on the screen to see anything on the screen?
What does it do if the camera not connected to JP3?
If you look at the power pins and the GND pins are setup for the JP3 header and the JP37 header, I would think the camera circuit may be damaged, and switched MOSFET for +INV POWER may be damaged.
The inverter is probably OK and not damaged when plugged into wrong connector JP3 but the power +5V line on pin 1 of the JP3 may have been grounded out.
You need to check the power pins of both headers. Things get damaged when power and GND pins are connected wrong to the loads.

The screen is completely black. I shined a bright light on the screen, and I did not see an faint image. The problem in the original post still occurs, if the camera is not connected to JP3.
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Old 09-23-2016, 04:32 PM   #4
49studebaker
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Default Re: KB925QF replacment

I connected an external monitor to the laptop's VGA port and nothing appeared on the external monitor's display.
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