12v Electrical problem

[Tamer11]

The 12v potable water pump keeps stopping on our boat. When I take a volt meter reading at the pump I get about 6 volts. I then take a reading from the 2 bayonet fittings that go into the rocker switch on the control panel and get 12 volts. I then connect the bayonet fittings back onto the rocker switch and the pump starts running (12 volts back at the pump) It will run for sometime and then it will stop again and only 6 volts can be measured at the pump again. I cannot find an in -line fuse. Is this a problem with the control panel and how do you trouble shoot it?

Thank's in advance

 

[Alex_Blackwood]

The 12v potable water pump keeps stopping on our boat. When I take a volt meter reading at the pump I get about 6 volts. I then take a reading from the 2 bayonet fittings that go into the rocker switch on the control panel and get 12 volts. I then connect the bayonet fittings back onto the rocker switch and the pump starts running (12 volts back at the pump) It will run for sometime and then it will stop again and only 6 volts can be measured at the pump again. I cannot find an in -line fuse. Is this a problem with the control panel and how do you trouble shoot it?

Thank's in advance

Possibly an old switch which has a bad internal contact, moving the connections may just correct it for a while . Can you take a reading from the switch with it all connected. See what you get in and what you get out. Is it single or double pole. i.e. does it switch the + or the + & -

 

[wingcommander]

What's the voltage at the switch or even at battery when pump fails. You could have a failing battery that initially reads 12v. But will rapidly drop with a discharge like a water pump..I discovered this on a recent trip. Battery read 12.6 , turned on plotter circa 4 amps plus water pump circa 6amp. Within 10 seconds plotter turned off due to bad battery...

 

[DownWest]

Has to be a bad connection. So, switch or any connection between it and the pump.

 

[greeny]

Has to be a bad connection. So, switch or any connection between it and the pump.

Not forgetting the return wire connections as well.

 

[Tamer11]

Thank you for the help, the switch is double pole and yes I think the it is playing up. Is I best to service it or just buy a new one?

 

[Alex_Blackwood]

Thank you for the help, the switch is double pole and yes I think the it is playing up. Is I best to service it or just buy a new one?

New one! Trying to service will probably be waste of time. Nothing to stop you playing with it once new is fitted, you may end up with a spare!

 

[PaulRainbow]

Thank you for the help, the switch is double pole and yes I think the it is playing up. Is I best to service it or just buy a new one?

Get a new one.

If it's for a pump and there are only two wires connected, you don't need a double pole switch