14
Troubleshooting
The following table lists the main causes of abnormal operation and the corrective measures required as well as the
protective circuit operation in each case.
Current Draw
PC9501N
PC6501N
PC4801N
Indicator Possible Cause Remedy Protection Circuit
CLIP indicator lights up
There is a short at the
amplifier’s speaker outputs, the
speaker’s inputs, or in the
wiring.
Locate and remove the short.
The PC limiter circuit activates
to protect the power transistors.
The impedance of the connected
speaker is too low.
Use a speaker with a minimum
impedance of 4Ω (8Ω in Bridge
mode).
PROTECTION indicator lights
up
The heat sink temperature has
exceeded 90°C.
Check the ventilation around the
amplifier and improve the
airflow if necessary.
The thermal protection circuit
activates to protect the power
transistors.
A DC voltage of ±2 V or greater
was detected in the amplifier’s
output circuit.
Consult your dealer or a Yamaha
service center.
The output relay activates to
protect the speaker system.
Line Current (A) Power (W) Thermal Dissipation
100/120V 230/240V In Out Dissipated Btu/h kcal/h
standby 0.08 0.04505174
idle 1.0 0.5 55 0 55 188 47
1/8 power 8 Ω/ch 8.2 4.5 500 250 250 853 215
4 Ω/ch 10.5 5.8 682 375 307 1050 264
1/3 power 8 Ω/ch 16.8 9.2 1093 667 426 1450 367
4 Ω/ch 23.7 13.0 1613 1000 613 2090 527
Line Current (A) Power (W) Thermal Dissipation
100/120V 230/240V In Out Dissipated Btu/h kcal/h
standby 0.08 0.04505174
idle 1.0 0.5 40 0 40 137 34
1/8 power 8 Ω/ch 5.4 2.9 375 188 188 640 161
4 Ω/ch 6.9 3.8 500 275 225 768 194
1/3 power 8 Ω/ch 11.4 6.3 820 500 320 1090 275
4 Ω/ch 16.4 9.0 1183 733 449 1530 387
Line Current (A) Power (W) Thermal Dissipation
100/120V 230/240V In Out Dissipated Btu/h kcal/h
standby 0.08 0.04505174
idle 1.0 0.5 40 0 40 137 34
1/8 power 8 Ω/ch 3.6 2.0 253 125 128 435 110
4 Ω/ch 6.2 3.4 444 200 244 834 210
1/3 power 8 Ω/ch 8.5 4.7 612 333 279 952 240
4 Ω/ch 15.0 8.2 1077 533 544 1860 468