SONY KV-28DS20
Manual de Servicio

Protection Error (Error 2):
Once every main loop (approximately 200ms OSD mode, 50ms text or menu mode), the micro checks the protection pin (pin 66). If the protection pin is high 6 successive times, a protection error is diagnosed. The protection pin is not checked during the first 3 - 4 seconds after AC on. If this error is diagnosed, the respective NVM register will be updated and the set goes straight into diagnostic standby with 2 flashes - no reset is attempted.

AKB Error (Error 5):
Once every main loop the micro checks the AKB stability by reading the IKR return from the Jungle IC. IKR=1 means that the AKB is stable, IKR=0 means that the AKB is unstable. If the AKB status is unstable for 10 seconds, an AKB error is diagnosed. AKB stability is not checked during the first 20 seconds after AC switch on. If this error is diagnosed, the respective NVM register will be updated and the response LED will flash 5 times continually, but the set will not go into standby mode. If the AKB status becomes stable, and remains stable for 10 seconds, the LED will stop flashing.

Time / seconds
0 10 20 30 40 50 60 70 80 90 100

IKR Return
A B C D E F

A. B. C. D. E. F.

IKR Return first goes high after 12 seconds. Micro begins checking IKR Return status 20 seconds after power on. Micro detects IKR return = 0. Micro detects that IKR has been 0 for 10 seconds; NVM counter is incremented and the LED starts flashing (flashes 5 times, off for 2 seconds, flashes 5 times, etc. Micro detects that IKR=1; LED continues to flash. Micro detects that IKR has been high for 10 seconds; LED stops flashing.

Startup Diagnostic Errors (Errors 6-18, 27, 29-32):
NVM 6 7 8 9 10 11 12 13 14 16 18 27 29 30 31 32 Error Description SCL pin low SDA pin low Both SCL and the SDA pins are low No acknowledge from the jungle (CXA2076) No acknowledge from the video switch (CXA2040) No acknowledge from the tuner No acknowledge from the MSP No acknowledge from the NVM No acknowledge from the CXA2089 video switch (DS20 & DX20) No acknowledge from the CXA1875 video Port Expander (DS20 & DX20) No acknowledge from the Dynamic Convergence (CXA8070) M3L_TXD pin low after Compact Text RAM test. M3L_TXD pin low M3L_RXD pin low M3LEN pin low Compact Text RAM test fail

If any of these errors are detected, the respective NVM register will be incremented. The software will then carry on with the power up sequence.

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