Service Guide
SP-i355
Version : 1.0
Page 8 of 15
1.2.2
Power LED (indicator) no light
Problem
Solutions
1.2.3 Volume , Tone no function
Problem
Solutions
Power LED (indicator) no light
Power switch or LED
defective
Defective
D1~D2, D4~D7,
U4
Ac cord of transformer
disconnected or defective
Re-solder or replace
defective component(s)
Analyzer and
Identify the Causes
Volume , Tone no function
Broken or short circuit
Defective U1, VR1, SW2, SW3
Check solder points on PCB
Analyzer and
Identify the Causes
Check and Replace defective
components
Check the
ac power
