Ok so bought this tv for £10 thought easy fix.
Powersupply is BN44-00168A
Mainboard is BN94-01325C
Checked the repair kit for this tv online.
Says to replace secondary side capacitors and if tv fails to power up replace the EEPROM IC1803 on the mainboard.
Being slightly naive I replaced the caps, tv still clicking, unhooked the mainboard and jumped pins 1-3 and the powerboard clicked on and didn't click off, I assumed it must be the mainboard so ordered a new EEPROM.
Few days later Installed the EEPROM and of course the TV still clicks.
Apparently according to another forum you can remove the EEPROM and power up the tv, if you get 'snow' ie analogue signal but no digital service. Then the EEPROM is at fault and needs replaced.
I removed the EEPROM completely and the tv still clicks away. Therefore I'm assuming the powersupply has an underlying fault.
I unhooked the mainboard again and jumped the powersupply on. I get the 5.2 standby voltage and the 5.4 volts, but don't get any 12 or 13 voltages, one of the grounds is also almost -1v
I noticed that the heatsink in secondary side with 2 Schottky diodes and ICM802 was burning hot, I removed both diodes and tested, both gave different readings so replaced them. Also decided to replace the IC as it was roasting.
Still clicking! Checked the ceramics and resistors close to the heatsink, nothing to report. Inspected for cold joints, nothing went over some anyway.
Granted, the caps I've used aren't the most reliable, but they all test great on ESR and capacitance. Also checked the main capacitor and all diodes in primary and secondary test good.
So at a loss with this one, kinda hoping someone has had a similar problem and found a fault.
EEPROM replacement.
Heatsink that gets roasting and replaced capacitors.
Powerboard
Soldering work on replaced caps, diodes and IC
Underside of board.
Any other pics required please ask.
Powersupply is BN44-00168A
Mainboard is BN94-01325C
Checked the repair kit for this tv online.
Says to replace secondary side capacitors and if tv fails to power up replace the EEPROM IC1803 on the mainboard.
Being slightly naive I replaced the caps, tv still clicking, unhooked the mainboard and jumped pins 1-3 and the powerboard clicked on and didn't click off, I assumed it must be the mainboard so ordered a new EEPROM.
Few days later Installed the EEPROM and of course the TV still clicks.
Apparently according to another forum you can remove the EEPROM and power up the tv, if you get 'snow' ie analogue signal but no digital service. Then the EEPROM is at fault and needs replaced.
I removed the EEPROM completely and the tv still clicks away. Therefore I'm assuming the powersupply has an underlying fault.
I unhooked the mainboard again and jumped the powersupply on. I get the 5.2 standby voltage and the 5.4 volts, but don't get any 12 or 13 voltages, one of the grounds is also almost -1v
I noticed that the heatsink in secondary side with 2 Schottky diodes and ICM802 was burning hot, I removed both diodes and tested, both gave different readings so replaced them. Also decided to replace the IC as it was roasting.
Still clicking! Checked the ceramics and resistors close to the heatsink, nothing to report. Inspected for cold joints, nothing went over some anyway.
Granted, the caps I've used aren't the most reliable, but they all test great on ESR and capacitance. Also checked the main capacitor and all diodes in primary and secondary test good.
So at a loss with this one, kinda hoping someone has had a similar problem and found a fault.
EEPROM replacement.
Heatsink that gets roasting and replaced capacitors.
Powerboard
Soldering work on replaced caps, diodes and IC
Underside of board.
Any other pics required please ask.
Comment