Banging noise when main turned on

[MDDog]

I have a Jayco Greyhawk 29 ME. Recently it has developed a loud bang when the main is first turned on. It bangs 10 times, every few seconds, when turned on and then it stops. Nothing else is turned on and it doesn't keep anything from operating. The only other issue happening is that my water pump is not coming on.

Anybody have any suggestions on what might be causing this noise?

[Vicr]

Main what??

[Kevin Cooper]

You need to give a complete explanation of what your issue is. No one can answer correctly without it.

[CAG]

https://www.mortonsonthemove.com/rv-water-pump-noise/

[MDDog]

Main electrical switch just inside the door, towards the floor. When turned on it displays alight. Have to have this turned on if you want the interior lights, the awning, the jacks - etc. to come on.

Not sure how I can be more descriptive. it's a series of 10 bangs with about 4 seconds between each when the main is first turned on. It only happens when the main is turned on and does not happen again unless you turn the main off and turn it back on.

That's the story...

[Kevin Cooper]

That is the battery disconnect switch. Electrically, “main” is in the electrical panel. That switch turns off the DC power from the battery to the panel and other items. Do the lights come on inside as soon as you hit the switch? Is it possible these “bangs” are coming from near your battery or near your electrical panel, or from under the hood near the engine?
Wild guess is that your disconnect solenoid is having trouble changing and closing. But will not know without answers to questions.

[craigav]

I will add that describing a sound with words can be challenging to start with. To me, a banging sound would be similar to someone hammering or perhaps someone loudly banging on the door, versus a clicking sound such as what the solenoid would sound like. My home audio system will make a solid thump when first powered on (not ten times though), perhaps some rv audio systems could do the same.

In any case, my suggestion would be to first attempt to determine where the sound is coming from. With that knowledge then it would be easier to consider what possible components are in that area that could make a sound when powered on. ~CA

[RPR]

Before turning the switch on is the water pump switch on or off. If on turn water pump switch off before turning “main” on. See if you still hear the bang noise.