PIONEER GM-X624

[mike49504]

THIS AMP DOES SOME WIERD STUFF..

THE AMP WILL POWER UP FOR ABOUT 5 SECS THEN THE POWER LIGHT STARTS BLINKING VERY FAST AFTER ABOUT 30 SECS THE POWER LIGHT WILL REMAIN SOLID AND THE AMP WILL POWER UP FO 5 SECS THE THE CYCLE REPEATS..

I REMOVED ALL OF THE OUTPUTS TO TEST THEM WHILE OUT OF THE AMP I TRYED POWERING IT BACK UP AGAIN AND IT DOES THE SAME THING..


WHILE THE AMP CYCLES I TRYED TESTING THE 494 AND ALL OF THE VOLTAGES ON ALL 16 PINS PULSE UP AND DOWN WHILE THE AMP IS DOING THIS

ANY IDEAS??

[Perry Babin]

Is the voltage pulsing on the B+ and ground terminals?

[mike49504]

No

[Perry Babin]

How much is the voltage dropping when it pulses?

IS the voltage pulsing on both the collector and the emitter of Q660?

[mike49504]

On pin 8 it will drop from 13.88 volts to 0 volts pin 4 will drop to -.68 volts


If i take the rectifiers out of the amp it will stay powerd up

Do not see a Q660

[Perry Babin]

I'm guessing that 4 and 8 are on the 494.

Reinstall the rectifiers and measure the DC voltage across the emitter resistors for each channel. Do you read anything more than 0.000 v DC on either channel?

[mike49504]

Found the problem R646 (10 ohm) resistor was bad