STR-DN840 (serv.man2) - Sony Audio Service Manual (repair manual). Page 5

– Continued on  page 6 – 

Check that voltages of the connector pins on the Digital  board are the following value.  DIGITAL board:  CN1501 pin 1, 2: +6.0 V  CN1501 pin 3, 4: +3.3 V  CN1501 pin 5, 6: +3.6 V  CN1501 pin 7, 8: +2.0 V CN1500 pin 3, 4: +3.3 V

Check that voltage of the following pin is 3.3 V, 1.3 V  DIGITAL board: IC3506  pin 112, 173: 3.3 V (Vout)  pin 18, 111, 116: 1.3 V (Vot) 

Check that voltage of the following pin is 3.3 V.  DIGITAL board: IC3000  pin 57: 3.3 V (INITX)  

Check that the X3000 on the DIGITAL board is oscillated  normally. 

Check the following parts and the surrounding circuit, and  exchange the defective parts.  DIGITAL board: IC3000 

Check the following parts and the surrounding circuit, and  exchange the defective parts.  DCDC board: IC1901, IC1902, IC1903, IC1904, F940,  F941 

Check the following parts and the surrounding circuit, and  exchange the defective parts.  DIGITAL board: IC3506 

Check the following parts and the surrounding circuit, and  exchange the defective parts.  DIGITAL board: IC3001, IC2100

Check the following parts and the surrounding circuit, and  exchange the defective parts.  DIGITAL board: X3000 

Perform the “SOFTWARE VERSION  DISPLAY MODE” (refer to page 14 on the  original service manual), and check that the  video micro-processor version is not “0.00”. 

Check that the sound from the  HDMI input is outputted.