STR-DH540 (serv.man2) - Sony Audio Service Manual (repair manual). Page 3

NG

– Continued on  page 4 – 

Check the following parts and the surrounding circuit, and  exchange the defective parts. DIGITAL board: IC2100        HP board: J101 MAIN board: Q375, RY921

Check the following parts and the surrounding circuit, and  exchange the defective parts. DIGITAL board: IC2100, IC2502

Check the following parts and the surrounding circuit, and  exchange the defective parts. DIGITAL board: IC2100, IC2104

Check the following parts and the surrounding circuit, and  exchange the defective parts. DIGITAL board: IC2100 MAIN board: IC400

Perform the “SOFTWARE VERSION DISPLAY MODE”  (refer to page 10 on the original service manual), and  check that the DSP version is not “0.00”.

Check that data is outputted from the following pins. DIGITAL board: IC2107 pin 16, 19, 20, 21

Check that sound occurs from the RY921 on the  MAIN board by inserting and removing headphone. 

Press the [MUTING] button on the remote  commander once, and check that the sound is  outputted from this unit. 

Explain the settings of this unit to the customer.  

Check that data is outputted from the following  pins.  DIGITAL board: IC2502 pin 48, 50, 41, 56 

Check that data is outputted from the following  pins.  DIGITAL board: IC2104  pin 15, 16, 19, 20, 21, 22, 26, 27 

Check that data is inputted to the following pins.  MAIN board: IC400  pin 63, 64, 66 ~ 73 

Check the surrounding circuit of power transistor  (example: Q600 on the MAIN board) and the  surrounding circuit of power amplifier circuit, and  exchange the defective parts. 

Press the [A.F.D.] button to select  the “MULTI ST”, and check that the  sound by various source (example:  coaxial input, analog input) is  outputted from all the channels (FL/  FR/SL/SR/SBL/SBR/C/SW). 

Check that voltage of pins of the IC2502 on the  DIGITAL board is the following value. pin 5: 1.1 V        pin 4: 3.3 V

Check the following parts and the surrounding  circuit, and exchange the defective parts. DIGITAL board: IC2100, IC2502, IC2503, X2500

Check the following parts and the surrounding  circuit, and exchange the defective parts. DIGITAL board: IC2100, IC2107, X2102

Check the following parts and the surrounding  circuit, and exchange the defective parts. DIGITAL board: IC2500 DCDC board: IC1902, IC1903