Marantz PM5005 Amplifier Repair (With Audio Tutorial)

Fault 1
Cross talk / bleed through from unselected channels.

Fault 2
Intermittent loss of Audio output when the Amplifier was powered up.
Turning the Amplifier On/Off multiple times would sometimes fix the issue for a short time.

Fault 3
Auto standby mode not working, Amplifier should switch to standby after 30 minutes when no signal input is detected.

Fault 1 and 2 was due to the failure of the positive 15 Volt regulator U8101, output was low at just over 3 Volts.

The input section IC as shown in the video requires a Plus and Minus 15 Volt supply to work correctly.

KIA7815 regulator replaced fixing the issues.

The remaining three other KIA series regulators were also replaced as they are known to fail.

Adjustment after repair
DC off set 0 mV +/- 3 mV and Bias 20 mV +/- 0.5 mV for each channel set back to factory settings.

Fault 3
Auto Standby Mode not working.

Auto Standby Mode first turned off
Press and hold SOURCE DIRECT for more than 5 seconds to turn the Auto Standby mode off.
The power indicator flashes once.
https://manuals.marantz.com/pm5005/NA...

Auto Standby Mode turned back on
Press and hold SOURCE DIRECT for more than 5 seconds to turn the Auto Standby mode on.
The power indicator flashes three times.
https://manuals.marantz.com/pm5005/NA...

No signals were connected to the Amplifier and after 30 minutes the Amplifier switched to Standby Mode power LED solid Red.

User controls and switches cleaned with De-Oxit to ensure noise free operation.

Amplifier fully tested working correctly.

For reference Dim Bulb Tester
Light Bulb Current Limiting Circuit (...

• #science_technology
• #marantz_audio
• #marantz_pm5005
• #amplifier_repair
• #amplifier_servicing