REPAIRING AND NOT THROWING AWAY

REPAIRING AND NOT THROWING AWAY

Richtige Fernseher haben Röhren!

Richtige Fernseher haben Röhren!

In Brief: On this site you will find pictures and technical information about Service Modes, Circuit Diagrams, Firmware Update procedure, Disassemble procedure, Universal remote control set-up codes, Troubleshooting and more....

If you go into the profession, you will obtain or have access to a variety of tech tips databases HERE IT IS Master Electronics Repair !.

These are an excellent investment where the saying: 'time-is-money' rules. However, to learn, you need to develop a general troubleshooting approach - a logical, methodical, method of narrowing down the problem. A tech tip database might suggest: 'Replace C536' for a particular symptom. This is good advice for a specific problem on one model. However, what you really want to understand is why C536 was the cause and how to pinpoint the culprit in general even if you don't have a service manual or schematic and your tech tip database doesn't have an entry for your sick TV or VCR.

While schematics are nice, you won't always have them or be able to justify the purchase for a one-of repair. Therefore, in many cases, some reverse engineering will be necessary. The time will be well spent since even if you don't see another instance of the same model in your entire lifetime, you will have learned something in the process that can be applied to other equipment problems.
As always, when you get stuck, checking out a tech-tips database may quickly identify your problem and solution.In that case, you can greatly simplify your troubleshooting or at least confirm a diagnosis before ordering parts.

Happy repairing!
Today, the West is headed for the abyss. For the ultimate fate of our disposable society is for that society itself to be disposed of. And this will happen sooner, rather than later.

How to use the site:
- If you landed here via any Search Engine, you will get what you searched for and you can search more using the search this blog feature provided by Google. You can visit more posts scrolling the left blog archive of all posts of the month/year,
or you can click on the main photo-page to start from the main page. Doing so it starts from the most recent post to the older post simple clicking on the Older Post button on the bottom of each page after reading , post after post.

You can even visit all posts, time to time, when reaching the bottom end of each page and click on the Older Post button.

- If you arrived here at the main page via bookmark you can visit all the site scrolling the left blog archive of all posts of the month/year pointing were you want , or more simple You can even visit all blog posts, from newer to older, clicking at the end of each bottom page on the Older Post button.
So you can see all the blog/site content surfing all pages in it.

- The search this blog feature provided by Google is a real search engine. If you're pointing particular things it will search IT for you; or you can place a brand name in the search query at your choice and visit all results page by page. It's useful since the content of the site is very large.

Note that if you don't find what you searched for, try it after a period of time; the site is a never ending job !

..............The bitterness of poor quality is remembered long after the sweetness of todays funny gadgets low price has faded from memory........ . . . . . .....
Don't forget the past, the end of the world is upon us! Pretty soon it will all turn to dust!

©2010, 2011, 2012, 2013, 2014 Frank Sharp - You do not have permission to copy photos and words from this blog, and any content may be never used it for auctions or commercial purposes, however feel free to post anything you see here with a courtesy link back, btw a link to the original post here , is mandatory.
All posts are presented here for informative, historical and educative purposes as applicable within fair use. NOTHING HERE IS FOR SALE !

Friday, 8 February 2019

SONY 32XBR400 _ 36XBR400 _ STANDBY LIGHT BLINKING & FAULT DESCRIPTIONS

SONY 32XBR400 _ 36XBR400 _ STANDBY LIGHT BLINKING & FAULT DESCRIPTIONS


SELF DIAGNOSTIC FUNCTION


When the TV shuts down and the standby LED blinks, the Main uCom IC701 knows which failure activated the shutdown. The number of times the Standby LED blinks indicates the problem board or section.

SHUT DOWN. STANDBY LIGHT DOES NOT BLINK AT ALL
  • The current on the +200 volt line is monitored by R8043 and Q8009. This 200-volt line supplies the High Voltage Converter stage, which feeds the flyback. A short in the flyback or excessive high voltage will demand sufficient current to shut down the TV. Since there is no connection to the Main uCom IC701, the standby LED will not indicate this failure.To determine if the +200V line to the HV Converter stage is causing shutdown, monitor the voltage at Q8009/Collector at power ON.  The voltage should not rise above 0.2Vdc at power ON. A higher voltage means the problem is on the D board in the Converter.

SHUT DOWN & STANDBY LIGHT BLINKS 2 TIMES
  • There are two +135V OCP monitoring circuits. The first circuit will cause the Standby light to blink [2] times and the second will cause the light to blink [7] times. Both sensing and output circuits are on the D board but the indicating circuit is on the A board.  CHECK R6598, R6591, Q6520, Q6521, and Q6524 monitor the current on the +135V line from the Secondary Power Supply. The +135 volt line supplies:
  1. Velocity modulation (V) board
  2. Horizontal  Output transistor (Q5030) and PWM (Q5003) stage (D board)
  3. The HOT supplies +200V to the RGB Output ICs (C board).
The blinking LED indicates the failure, but the problem could be in one of three locations: The H. Output/PWM stage, the sensing circuit on the D board, or the sensing circuit on this A board. Verify this problem by monitoring CN6506/pin 8 as you power ON. If the voltage does not rise above 0v at power ON, the problem is not on the +135V line. If the voltage reaches 1.2V, disconnect the V board and try again. If the CN6506/ pin 8 voltage still rises to 1.2V, test the H Output and PWM transistors or replace the entire D board.

SHUT DOWN & STANDBY LIGHT BLINKS 3 TIMES.
  • There are two possible causes for this LED indication caused by excessive voltage. Two power supply voltages are monitored, +135V on the D board and unregulated 7V on the A board. On the D board, the maximum voltage on the +135V line is +140V. This is monitored by IC6505 and Q6522. On the A board, the maximum voltage on the unregulated 7V line is 8.2V. This is monitored by D6014.  The problem can be on either the A or the D board. Locate D6017/Cathode or D6014/Anode and monitor this voltage as you power the TV. If the voltage rises above 1V, the problem is in the A board’s power supply (regulation). To test the power supply on the D board, monitor CN6506/pin 7. If this voltage rises above 0.6Vdc, the problem is on the D board.
SHUTDOWN & STANDBY LIGHT BLINKS 4 TIMES

  • A vertical failure because of the output IC or power supply (both on the D board) will cause the Y/C, CRT Drive IC201 to send emergency data to Main uCom IC701. IC701 turns the TV by opening the AC relay (IC701/pin 69 goes LOW).  Measure the +15v and -15V to the vertical output IC5004/pins 2 and 4 before you suspect the IC5004 itself.

BLANKING & STANDBY LIGHT BLINKS 5 TIMES
  •  The Ik signals are measured by Y/C, CRT Drive IC201 and are used to adjust the RGB gain to maintain color balance. As the picture tube ages, the Ik signals may fall below the threshold for automatic balance and mute/blank the picture.  Increase the G2 control on the CRT’s C board. If that does not return cathode current to within operating range so the picture will appear, examine each filament to see if it is lit.
  • Then use oscilloscope to examine the signal to the cathode. Go to CN9001/ pins 1, 3 and 5 to see if there is a signal coming into the C board. Next check the signal at the CRT cathodes. If they are present, check the IK signal from CN9001/pin 8 of the C board. You should see three pulses and be able to change the level of the signal with the G2 control. If you get about 1Vp-p pulses at pin 8, this is the normal output from the CRT/C board so the problem is on the A board about IC201.



SHUT DOWN & STANDBY LIGHT BLINKS 6 TIMES
  • IC701/pin 43 monitors the Set 5V supply from the power supply on the A board. This voltage feeds almost all the boards. A short on the Set 5V line will cause IC701 to shut off the AC relay (IC701/pin 69 goes LOW).  At power ON, measure the “Set 5V” at regulator IC6007/Output on the A board. The trip voltage is 3.7Vdc. If this voltage remains low at power ON, unplug the B board within the A board and power ON again.

SHUT DOWN & STANDBY LIGHT BLINKS 7 TIMES
  • There are two +135V OCP monitoring circuits. The first circuit will cause the Standby light to blink two times and the second will cause the light to blink seven times. Both sensing and output circuits are on the D board, but the indicating circuit is on the A board.  The second OCP circuit monitors the current through the PWM Output (Q5001-3) that supplies B+ voltage to the H. Output transistor Q5030. When there is excessive current drawn by the Horizontal Output stage, Q5018 turns OFF, permitting IC201/pin 34 to rise to a threshold of 1.2Vdc. IC201 blanks the picture to prevent a CRT line burn and sends data to IC701/pin 30 to shut down the TV.  Q214 is turned on for five seconds at power ON to permit comparator IC5007 time to stabilize. 
  • If the Standby light blinks two or seven times, the problem is most likely on the D board where the sensing and Horizontal Output stages are. On the D board, if the Horizontal Output (Q5030), PWM (Q5003) transistors, and video output ICs (C board) are good, suspect the components in the sensing circuit (same board). The sensing parts are Q5004, IC5007 and Q5018.
  • Verify that this circuit is causing the shutdown by disconnecting the H. Output Transistor Q5030 and monitor the voltage at CN5505/pin 8 as you power ON. If this voltage rises above 1 volt, this +135V OCP circuit is responsible. Suspect Q214 on the A board and the following main parts on the D board: R5013, Q5004, IC5007, delay cap C5006, Q5018.
Posted By: FRANK at 06:47
TAG: , , ,