Sony XBR-75X940C 4 RED Blinks No blacklight

[lniSonyBad]

TV clicks when turned ON and in a few seconds clicks again and blinks red 4 times. I see no light from the panel.

I downloaded the service manual and tried the step of checking R90c7 on the main Board and the voltage is above 0.898 V which indicates LED Driver or G Board. I replaced the G6 Board just in case but same thing happens. Maybe is another G Board?

I measured the BL_ON and shows 3.3V before going to zero when red light comes.

I tried to ground the BL_ERR and LED_ERR signals but no change.

I cannot find the LED driver board 15ST084A-A01 for this TV anywhere so my only option is to see if I can find what is wrong on it (if indeed this is the issue)

There is only one capacitor on it which I replaced to no avail.

I am looking for suggestions on how to identify the defective component on that LED Driver board if possible. I suspect is something quite central as there is no backlight at all

PS. For service manual google "sony_xbr-65x930c_75x940c_75x945c_chassis_gn1t_ver.2.0_segm.xs_sm" and first hit is from ElektroTanya

[budwich]

Re: Sony XBR-75X940C 4 RED Blinks No blacklight

take your meter and measure all the label pins identifiedat the connectors at the power board at "power off / plugged in" and at "power on". Note some change rapidly so you need to be monitoring the voltage on your meter immediately at power on. Measuring the BL-err as opposed to shorting it (not sure what that would do / help) will tell you what's up with the BL. Further the voltage connector from the power board to the BL booster board has voltages associated with it that help identify. Provide close ups and the connector area / labeling to help the forum.