Marantz SR4002- Tried to reset,but resetting didn't work do I have a amp problem?Tried pushing and holding down these 3 buttons s.speaker b and att and exit buttons for at least 3 sec , unit turned back on for 5 seconds and then said , " protect " and turned off Then tried pushing and holding down mult speaker and exit and att buttons together for at least 3 or more seconds. Nothing happened , standby light still flashing

SOURCE: Power is connected to unit.

The unit is in "protect" mode. This means that there is a problem in the final output section. The most common fault is bad output transistors. Expect a parts cost of abput $15-$30 in parts plus the local labor rate for a repair cost.
Dan

SOURCE: marantz sr4002 amp standby light flashing

did you ever find a solution? I am having the same issue. [email protected]

SOURCE: Marantz sr4002 - Power light

Generally speaking, an amp attempts to protect itself from heat, shorts, overloads and operator exuberance by refusing to turn on or stay on.

Overloads can be from excessive periods of high output or marginally low impedance loading by the speakers; and shorts would be wiring issues or a speaker blowing up.

You should be able to feel if it's hot. WHY is it overheating? Make sure it has sufficient ventilation on all sides and that vent holes are not blocked by dust balls. Ensure the fan (if equipped) is running as designed (some only operate on demand). Clean dust and debris from it.

If the amp comes back on after cooling, you're lucky. They only have so many self-protection cycles in their lives so continuously resetting or cycling their power without addressing the cause can do more harm than good.

If it protects immediately on a cool power up you should disconnect the speaker connections and try it 'nekkid'. If it comes up then diagnose which lead(s) are shorted. If it does not come up the problem is internal and should be left to an experienced and competent hands-on tech.