Samsung HT-C553 Service Manual page 76

4-2 Measures to be taken when the Protection Circuit operates
4-2-1 SMPS Protection
The Condition of Power Protection Active.
1. Voltage of SMPS's +, - PVDD (+30V, -30V) is higher or lower than Standards
Normal Condition Voltage Range: PVDD (+30V, -30V): about +30V, -30V
2. Over-current occurs to FET (Over-output or Output short)
3. FET's temperature exceed 150°C.
4. No supply voltage on GATE DRIVER.
4-2-2 AMP Pre-Inspection relating to Power Protection
If you think, there are problems at the AMP PCB, you can check the pcb without disassemble the set.
(Caution!!: Do not connect the power cord during bellow test!)
F/R CH
CENTER
SUBWOOFER
If Measured Resistance is very different from above numbers. There is a Problem.
→ AMP PCB Problem
Samsung Electronics
Measurement Resistance using Tester
C550
1.8Ω
1.8Ω
1.8ΩΩ
5.1CH SPEAKER OUTPUT
FRONT R
GND
REAR R
C650
1.8Ω
1.8Ω
1.8Ω
<Table 4-1>
CENTER
SUBWOOFER
Troubleshooting
- Approximately
C450
1.8Ω
1.8Ω
1.8Ω
FRONT L
REAR L
4-17