Sony KDL-40S5100

[budm]

Re: Sony KDL-40S5100

Check Transistor Q6400 to see if it shows low resistance (set meter to Ohm mode) between E and C.
Check the DCV of the Q6400 E-B junction (Voltage between Base and Emitter) to see if it is being turned on or not, it should be OFF in normal operation.
If Q6400 is ON it will take the Enable signal to GND.

[shadetreetrader11]

Re: Sony KDL-40S5100

No voltage on pin 6 of IC6700 to GND pin of connector CN6701

[budm]

Re: Sony KDL-40S5100

OK, so it does 5VDC for the IC 6700 to run, check the Enable pin 6 to see if it is getting 2 ~ 3 Enable Voltage or not.

[shadetreetrader11]

Re: Sony KDL-40S5100

Checked R6700 and It was good. Couldn't find R6766 but found R6765, On the schematic you sent me R6766 was the next component inline from the vcc_12 pin. My board has R6765 as the next resistor after the VCC pin. It messured 4.7ohms. I put a 600 ohm resistor from 3.3 standby to power on. Then messured the voltage from pin 20 of IC6700 to ground and it was 5.01 volts.

[budm]

Re: Sony KDL-40S5100

OK check these parts on the power supply board:
1) Check resistance of Fusible resistor 4.7 Ohm fusible resistor R6700.
2) Check resistance of Fusible resistor 1 Ohm fusible resistor R6766
3) Check DCV at pin 20 of IC6700 against GND pin of connector CN6701 to see what you have.

[shadetreetrader11]

Re: Sony KDL-40S5100

And the backlight doesn't flash at all. The main caps do jump to 390 when you push the power button

[shadetreetrader11]

Re: Sony KDL-40S5100

I don't see any lights blinking

[budm]

Re: Sony KDL-40S5100

See post 14.

[shadetreetrader11]

Re: Sony KDL-40S5100

CN6150

Reg 12v 12
Reg 12v_gnd 0
Unreg 15v_gnd 0
Unreg 15v 15.1
standby 3.3
Ac_off_detect 3.3
Power_on 3.3

CN6701

Vcc_12 11.9
fb 0
fb 0
gnd
gnd
ld 11.3
ld 11.3


cn6154

dim starts at 1.5 and slow drops after a few secs
bl on 1.15
inv err 1.95
balancer err 0
standby 3.3
Ac_off_detect 3.3
Power_on 3.3

[budm]

Re: Sony KDL-40S5100

Your TV has blink codes, can you tell us what it is right now?

[budm]

Re: Sony KDL-40S5100

Well, you better report ALL the Voltage on ALL the pins of all the connectors on the cold side again then, bad DATA does not help troubleshooting the problem.
If you look at the TV in the dark room, do you see the backlights even flash on for seconds when you turn the TV on?

[shadetreetrader11]

Re: Sony KDL-40S5100

Stop!!!! I messed up big time. I'm sending you all on a wild goose chase. I DO have reg 12V on CN6150. I'm so sorry.

[budm]

Re: Sony KDL-40S5100

The reg 12V is generated by the same transformer for the 15V, since you are getting the VC12V OK, then you need to check the DCV at both pins of the inductor L6151, it should have 12VDC on both pins, the output pin of that inductor is connected to the REG12V pins.

[shadetreetrader11]

Re: Sony KDL-40S5100

Is the unreg 15v_gnd supposed to come from the psb or the main board?

[shadetreetrader11]

Re: Sony KDL-40S5100

diodes tested good and the P/N on the board is a A1660720B 903963

[budm]

Re: Sony KDL-40S5100

So what is the power supply board P/N as printed on the barcode sticker?

[dick_barton]

Re: Sony KDL-40S5100

Have you checked D6150, D6151, D6152 which I believe rectify the secondary voltages

[shadetreetrader11]

Re: Sony KDL-40S5100

Thats correct

[dick_barton]

Re: Sony KDL-40S5100

So you have VCC_12 at the CN6701 connector but the Reg 12Vis missing at the CN6150 connector. Have I read it right?

[shadetreetrader11]

Re: Sony KDL-40S5100

CN6701

Vcc_12 11.9
fb 0
fb 0
gnd
gnd
ld 11.9
ld 11.9


cn6154

dim starts at 1.5 and slow drops after a few secs
bl on 1.15
inv err 1.95
balancer err 0