Sony KDL-46Z4500 Completly Dead

[budm]

Re: Sony KDL-46Z4500 Completly Dead

I got it download now and looking to see how the circuits are connected.

[budm]

Re: Sony KDL-46Z4500 Completly Dead

OK, you can power up the power supply board by itself to check the voltage. From what I can see from the picture: the + output of the bridge is fed to L6500, output side of L6500 is fed to Inductor L6504 PIN 1, the output pin 6 is connected to 1/2 of D6502 (Dual diode with common Cathode) to produce the DC voltage of 1.414 x line voltage to produce DC voltage on C6529/6530 before the PFC voltage booster is kick in, so if you do not have about 330VDC on C6529/6530, you need to check D6502. It is very simple rectifier setup. The L6505 pin 6 is also fed by the + from the bridge, the output pin 1 is fed to the other half of D6502 for using in the PFC voltage booster circuit driven by Q6500.
So when you apply 230VAC to the board, you must have the DC on those two 450vdc cap right away. and have the STBY voltage (produce by IC 6200, T6200) on pin7 (STBY) of CN6150.

[max1636]

Re: Sony KDL-46Z4500 Completly Dead

OK, you can power up the power supply board by itself to check the voltage. From what I can see from the picture: the + output of the bridge is fed to L6500, output side of L6500 is fed to Inductor L6504 PIN 1, the output pin 6 is connected to 1/2 of D6502 (Dual diode with common Cathode) to produce the DC voltage of 1.414 x line voltage to produce DC voltage on C6529/6530 before the PFC voltage booster is kick in, so if you do not have about 330VDC on C6529/6530, you need to check D6502. It is very simple rectifier setup. The L6505 pin 6 is also fed by the + from the bridge, the output pin 1 is fed to the other half of D6502 for using in the PFC voltage booster circuit driven by Q6500.
So when you apply 230VAC to the board, you must have the DC on those two 450vdc cap right away. and have the STBY voltage (produce by IC 6200, T6200) on pin7 (STBY) of CN6150.

Thanks again for the help it's very much appreciated. I will check the voltages now.

[max1636]

Re: Sony KDL-46Z4500 Completly Dead

Well... Everyones going to get a laugh out of this, I laid the board upside down on the TV on a cloth and plugged in the mains, except I plugged the mains into the PFC plug instead tripping the breaker out... The caps now don't charge at all, I get zero, and measuring from the output side of the bridge with the ground on the TV chassis I get about 10v AC (Corrected, AC not DC), The problem is I don't know if that issue was there before because I hadn't checked any of the main components voltages before. I will start by checking the bridge would that be a good idea?

[budm]

Re: Sony KDL-46Z4500 Completly Dead

As indicated in my post 5, you cannot use the chassis as the ground ref point when working on the primary side (hot side) of the circuit, the negative leg of the main filter cap is the ground ref point for the primary circuit. The cold side you can use the chassis as the ground ref point. I hope that you did not report the voltage reading on the main filter cap using the chassis as the ground ref point at the beginning of the post when I requested the voltage readings on those two main filter cap. The 230VAC (330V peak) feeding into the DC PFC out put can really do lots of damages. I think you will be going to buy the new board.

[max1636]

Re: Sony KDL-46Z4500 Completly Dead

As indicated in my post 5, you cannot use the chassis as the ground ref point when working on the primary side (hot side) of the circuit, the negative leg of the main filter cap is the ground ref point for the primary circuit. The cold side you can use the chassis as the ground ref point. I hope that you did not report the voltage reading on the main filter cap using the chassis as the ground ref point at the beginning of the post when I requested the voltage readings on those two main filter cap. The 230VAC (330V peak) feeding into the DC PFC out put can really do lots of damages. I think you will be going to buy the new board.

I think you are right which is really disappointing I was looking forward to fixing it. When measuring the caps I used the pos and neg which I always have it was only when measuring the bridge I was using the chassis. The bridge appears to be fine I will let you know anything else I find.

[budm]

Re: Sony KDL-46Z4500 Completly Dead

Check D6502.

[max1636]

Re: Sony KDL-46Z4500 Completly Dead

Check D6502.

Maybe I should just admit defeat. I barely getting anthing on D6502, hardly anything is going into the bridge and hardly anything is coming out, and just as a final screw you I went to meter one of the 0.22 Caps and it fried my ESR Meter.

[selldoor]

Re: Sony KDL-46Z4500 Completly Dead

How about starting over ?

Connect it all up

Test for AC on both sides of the mains fuse.
Meter on V600AC Black lead on mains negative socket probe fuse with red probe.

Next meter on 600vDC test voltage on both main caps

Which reminds me can we have a straight on picture of the Top side of your actual board.

Budm has said the voltage should be at the caps as soon as you switch on so if it is not then go back to the bridge.

First ,Meter on vAC600 test the inner pins for mains voltage
If that is not there then we need to find put why.

If it is there then meter on vDC600 test across the outer pins

(( I am not sure why you would be testing the output voltage using AC as the output is DC unless you were looking for high ripple? ))

I have posted a picture here of the bottom of your board. to help others when your links disappear not as sharp as the html but better than nothing

KDL46Z4500 1 877 271 12

KDL46Z4500 1 877 271 12

[max1636]

Re: Sony KDL-46Z4500 Completly Dead

The board is now working and the TV turns on!! After being frustrated with the board and leaving it for some time I went back to it a few hours ago for a final look at it. If you read back you will see I accidentally put mains power to the PFC Out Pin instead of the 240 Input (Oops) leaving me in an even worse situation than before. Previously the board would give a very small voltage to the 450v Caps but after putting mains to the PFC out I wasn't getting anything even at the bridge rectifier. I found that a 6.8 Ohm Ceramic Resistor had blown which I replaced, which then blew again. I probed the DC Side of the bridge rectifier and was getting about 8.75 k Ohms which I though was unusual. I traced the short back to a pair of K3561 Field effect transistors which I replaced with K3563's from another faulty board, I then replaced the 6.8 Ohm Ceramic resister which this time did not blow and I was now getting 330v DC at the 450v Caps. I connected the board to the TV and it came on but it only stays on for about 30 seconds before shutting off and blinking 6 times which according the service manual indicates a backlight error. Could this be because I have used different field effect transistors? I will be working more on the TV later but wanted to hear any suggestions.

[max1636]

Re: Sony KDL-46Z4500 Completly Dead

I've read a few voltages from the board. Standby is fine, 12v is fine. I'm getting 450v AC going into the inverter board the only thing that seemed strange was that from the PFC connector I'm getting 388v DC when on the board it says it should be 375v. Could the different FET's be causing this and giving it just enough to trip the set out?

[max1636]

Re: Sony KDL-46Z4500 Completly Dead

At the Inv_ERR pin I get 1.7v in standby mode but when the set comes on I get almost zero volts. But at the Balancer Error pin the voltage rises to 5v before the set shuts off. So I'm not sure the FET's I replaced are the issue. Maybe the TV had this problem before it died completely.

[Brighton Mike]

Re: Sony KDL-46Z4500 Completly Dead

Has there been a resolution to this problem

[Brighton Mike]

Re: Sony KDL-46Z4500 Completly Dead

I have the same problem on the KDL-40Z4500 and have found R6022 6R8 5watt open circuit. I don't know if there are any more problems, as I'm waiting for the resistor to arrive.

Regards,
Mike

[Brighton Mike]

Re: Sony KDL-46Z4500 Completly Dead

Resistor solved the problem. Set now working.......

[budm]

Re: Sony KDL-46Z4500 Completly Dead

What Voltage do you get between the two legs of the resistor?

[Brighton Mike]

Re: Sony KDL-46Z4500 Completly Dead

budm I don't know what the voltage was as I never measured it, but I can tell you that I traced out the circuit and it was directly across the relay contacts. Clearly the resistor is used in standby mode (relay not energised) and is shorted out by the relay when in run/on mode.

Mike

[budm]

Re: Sony KDL-46Z4500 Completly Dead

OK the resistor is used for limiting the inrush current, when the relay is turn on (to get full power to run the TV) the contacts of the relay will bypass the resistor so the resistor will be out off the circuit, but if the relay has bad contacts, then you will have Voltage on the resistor and that can cause it to go open circuit due to to much current.
You can verify if the relay contacts are OK or not by measuring the Voltage drops across the resistor, it should be 0V if the relay contacts are OK.

[Brighton Mike]

Re: Sony KDL-46Z4500 Completly Dead

budm I totally agree, I did remove the relay when I had the problem energised it and the contact resistance was measured at 0.02 ohms

Mike