Yamaha XP3500 User Manual

The following table lists the main causes of abnormal operation and the corrective measures required as well as the protec-
tive circuit operation in each case.

● XP3500, XP2500

● XP7000, XP5000

CLIP indicator lights.

There is a short at a speaker ter-
minal, amplifier terminal, or wire.

Locate and correct the cause of 
the short.

The PC limiter circuit 
operates to protect the 
power transistors.

The amplifier load is excessive.

Use a speaker system with an 
impedance of at least 4 

Ω (STE-

REO/PARALLEL mode) or 8 

Ω 

(BRIDGE mode).

TEMP indicator lights.

The heat sink temperature has 
exceeded 85°C (185°F).

Check the ventilation slots, and 
provide better airflow around the 
amplifier.

The TEMP indicator 
lights up to indicate tem-
perature warning.

PROTECTION indica-
tor lights.

The heat sink temperature has 
exceeded 90°C (194°F).

Check the amplifier ventilation 
conditions and take appropriate 
measures to improve the airflow 
around the amplifier.

The thermal protection 
circuit operates to protect 
the power transistors.

PROTECTION indica-
tor lights.

A DC voltage of +2 V/-2 V or 
greater was generated in the 
power amplifier’s output circuit.

Consult your dealer or the near-
est Yamaha service center. 

The relay operates to 
protect the speaker sys-
tem.

Power has been shut 
down. (All indicators 
are off.)

A DC voltage of +2 V/-2 V or 
greater was generated in the 
power amplifier’s output circuit.

Consult your dealer or the near-
est Yamaha service center.

The protection circuitry 
shut off the power to pro-
tect the speaker system.