Walter, From Tech Repair CD: ZENITH\IQB50M92W\DEAD\\\\LEAKY C3407* C3408(100/25V)\\\\\\\\ ZENITH\IQB50M92W\DEAD SET-NO LED'S LIT\\\\SHORTED IC901 REGULATOR AND OPEN PROTECT E991\\\\\\\\ Jeff Dougherty Intrepid Video TV/VCR 263 S Front St Steelton PA 17113 fax...717-564-4952 www.intrepid-video.com www.tech-repair.net ----- Original Message ----- From: "walter wood" <wwood_38478@xxxxxxxxx> To: "Tech Assist" <techassist@xxxxxxxxxxxxx> Sent: Saturday, November 15, 2003 6:10 PM Subject: [TechAssist] Zenith IQB50M90W strange happenings. This is the Hitachi made for zenith. Zenith manual calls it the ZP88,90,and 92 chassises. It's more like the Hitachi AP73/74 series than the AP8xxx and AP9xx. Set came in with total convergence failure, but did play. For no reason that I can think of, it is now a dead set. I went ahead and replaced reset ic and diode that is supposed to fix the convergence. I've also replaced regulator I901. Trying to follow the diagnostic LEDs is impossible, and I hope someone has some ideas. The front led is not lit, but pulses ON briefly when most of the green leds go OFF. I say most because D947 is ON all the time. D946 turns ON briefly as the rest of the green leds turn off. The red protect D912 is ON DIMLY while all the green leds but D964 are ON, but Flashes bright, as the Green ones go off then it(the red) turns OFF. It repeats this cycle on and on. Of course the troubleshooting chart has nothing about this kind of behavior interpiting the leds fault. The regulator I901 has 177vdc on pin 1 and it does not vary. The other pins seem ok voltage wise except pin 5 which is about half what it should be. These do turn off and on where pin 1 does not. Over on the secondary the voltages are down by more than half and turn on and off. Horizontal output seems ok, and I don'e see any bad solder. I'm stuck!! TIA Walter ===== Walter Wood Future Tech Home Center 2786 Hwy. 43 N. Lawrenceburg Tn. 38464 931-829-3337 Fax 931-829-4044 mailto:wwood_38478@xxxxxxxxx __________________________________ Do you Yahoo!? Protect your identity with Yahoo! Mail AddressGuard http://antispam.yahoo.com/whatsnewfree ***************************************************************************** Classifieds! Buy or Sell! http://sell.tech-assist.org The Tech Address Book: http://www.tech-assist.org/secure/tip/contact.htm Add a Repair Tip Here, or Change/Remove your Email Address: http://www.tech-assist.org/secure/tip/main.htm Lost Password: http://www.tech-assist.org and select "Lost your Login Info?". Email Archives: //www.freelists.org/archives/techassist/ ***************************************************************************** Classifieds! Buy or Sell! http://sell.tech-assist.org The Tech Address Book: http://www.tech-assist.org/secure/tip/contact.htm Add a Repair Tip Here, or Change/Remove your Email Address: http://www.tech-assist.org/secure/tip/main.htm Lost Password: http://www.tech-assist.org and select "Lost your Login Info?". Email Archives: //www.freelists.org/archives/techassist/