Head Switch- no power

[JLR]

Came down to boat after a three week hiatus and my VIP head switch has no power. The solenoid is good, the GM pump is good, the switch is good, the on/off toggle is good but no power. The foregoing was confirmed when I jumped power from the sump switch. I have not pulled the breaker to see if that is good but I am thinking that is an unlikely source of the problem. The power to the head switch is supplied by a brown jacketed wire with two hots on the inside. One hot goes to the sump switch and is working. The other goes to the head switch and has no power. Needless to say, tracing the wire to the breaker is quite the task and if there is a terminal block, that too is buried somewhere inaccessible. I am pulling the manual as I type this but am pretty well out of any ideas other than a broken or corroded wire somewhere where the non head end of the brown jacketed wire is connected to a terminal block. Any ideas?

 

[davidwigler]

Did you check the solenoid input with a voltage meter? If it has no current how do you know it is working? If no current to the solenoid, check for current at the breaker. No need to remove it.

 

[JLR]

Mechanic said he could hear solenoid working. I have not yet checked for power at the breaker. The solenoid was my first suspect. Perhaps someone could tell me how the power gets from the breaker to the pump. I have about 5 volts on the lead to the switch when it should be 26 volts or so. Also, although I know the momentary switch is working because I can hot wire it to work, I am surprised that there is continuity between the to leads to the momentary switch. Is this normal? I am surely tempted to simply jump the hot lead from the shower sump but I do NOT want to leave any wire that is supossed to be hot somewhere it is not supposed to be.

 

[piripucha]

Check the solenoide by jumping the small positive terminal with the large one. If the pump turns is not on the pump side. I had the same problem when I did not use the pumps for 2 month in my case the pump got stuck I had to turn it by hand. I hope this helps.

 

[davidwigler]

If he heard the solenoid click it is getting power so it is not the breaker or wire to the pump. Check all the connections at the pump and the solenoid for tightness and corrosion. Those crimped ring terminals can corrode through. Check the voltage at the pump while someone pushes the switch, and work your way back. My guess is a bad solenoid. I had one go bad. It would click but not open the circuit.

 

[tonytrakovich]

The solinoid will have two large terminals and two small ones. The two small ones are for the coil. There will be a positive and a negative. Since you hear a click when the button is depressed, the coil is probably working properly. The large terminals handle the high current of the head pump. One terminal should be hot +24v as long as the head breaker in the engine room is on. The other terminal will be hot when the button is pushed and the coil is energized. If one is hot and the other is not (when button is pushed), then the solinoid is bad. If the other terminal is hot then check voltage at motor. Motor will have a stud for positive and neg wires. Check voltage there when button is depressed. If there is voltage and pump is not working, then it is either a bad pump, a locked rotor, or corroded connectors / wire allowing voltage but not enough current to motor.

 

[Tim Powell]

The solinoid will have two large terminals and two small ones. The two small ones are for the coil. There will be a positive and a negative. Since you hear a click when the button is depressed, the coil is probably working properly. The large terminals handle the high current of the head pump. One terminal should be hot +24v as long as the head breaker in the engine room is on. The other terminal will be hot when the button is pushed and the coil is energized. If one is hot and the other is not (when button is pushed), then the solinoid is bad. If the other terminal is hot then check voltage at motor. Motor will have a stud for positive and neg wires. Check voltage there when button is depressed. If there is voltage and pump is not working, then it is either a bad pump, a locked rotor, or corroded connectors / wire allowing voltage but not enough current to motor.

way to go Tony grate explanation!!

 

[JLR]

Thanks Tony. Still betting on a corroded splice in the wire somewhere. Will likely run an entirely new wire.o

 

[JLR]

Large gauge wire from breaker to solenoid is fine. Large gauge wire from solenoid to pump is fine. One of the smaller trigger wires going to the solenoid from the switch is dead. It will be replace. Thanks for all of the help.