Hi there .......my sa gx303P stereo amplifier/tuner technics ...the cooling fan for the power amplifier works only on a somewhat strong signal .....if you play soft music at low volume the cooling fan doesn't get triggered on ......sounds ok but if you forget to shut amplifier down it's already overheated severely because of the fan staying idle with the power amp still active ........can I modify this condition and see that the fan is always on ?

I followed up on a tip on fixya .......I am currently monitoring the problem to see if further work is necessary ..

This unit has a fan that only works under a relatively high volume setting , ........it would be perfect if the user played the unit on a high volume setting........nevertheless low volume settings should not cause the unit to overheat........The heat detector circuit may be defective if it does so .......or you may have a speaker mismatch causing a high load on the output thereby causing it to work harder and eventually overheat

These units are designed to only run the fan when necessary. If the unit is overheating, there is a problem in the detection circuit. This is a relatively inexpensive repair. If you are getting overheating when running at a low volume, it suggests that the speakers are not matched to the amp. In other words, the amp is expecting an 8 ohm load and is being presented a lower ohm load. This makes the amp work harder and generates more heat. Check the speaker wires and make sure that they are not frayed or crossing in any manner. Also, verify that the rating of the speakers is correct.

Update this with what you find.

Thanks,
Dan