Front jacks work on 110v but not on 12v

[Edgeworld]

The front jacks on 2010 mountaineer 5th wheel don’t work on 12v,on 12v the power goes off,comes back on. 110v works like normal? Any ideas were to start?

 

[ChuckS]

First thing I’d check is the charge status of the battery..

The converter output when on shore power is most likely making up for the low battery voltage hence no issue when on shore power

I’d also be checking the battery terminal connections for evidence of corrosion , loose , and the battery to chassis frame ground connection

Remove the chassis ground connection and clean the paint off of the frame and reinstall

 

[BB_TX]

Put a voltmeter across the battery and monitor that voltage while someone tries your jacks. If that voltage drops low when the jacks are actuated you have a low battery. At best needs charging. At worst needs replacing. Take it and have it load tested.

 

[JoeO-MOC]

The front jacks on 2010 mountaineer 5th wheel don’t work on 12v,on 12v the power goes off,comes back on. 110v works like normal? Any ideas were to start?

Possibly check the thermal overload in the front compartment. Factory used to be 50 amp and would go bad. I replaced mine with 70 amp and have not had a problem since.

 

[DABOO77]

Put a voltmeter across the battery and monitor that voltage while someone tries your jacks. If that voltage drops low when the jacks are actuated you have a low battery. At best needs charging. At worst needs replacing. Take it and have it load tested.

I agree with watching battery voltage while in use. First try on batteries alone, if voltage quickly drops from 12 to anything less then 9.5 and continues to drop I'd replace batteries. Obviously that's taken into account cable connections are clean and tight at all points. Because of the typical nature of use, even quality batteries only last 3 to 5 years in my experience. I do run a pair of group 27 batteries in my unit.

 

[Daryles]

LCI put out a TSB years ago to put the hydraulic pump on its own 80A circuit breaker.

Carl wrote the
Perfect 12vdc troubleshooting flow chart:

2011 Montana has no 12 volts with shore power connected even with battery power 12.7v

Can’t figure out why I have no 12v power

www.montanaowners.com

 

[Edgeworld]

It fixed it self ,works on both

 

[Edgeworld]

The front jacks on 2010 mountaineer 5th wheel don’t work on 12v,on 12v the power goes off,comes back on. 110v works like normal? Any ideas were to start?

It fixed it self, works on both

 

[BB_TX]

That’s good. And not good.

If it’s working you can’t troubleshoot it to determine what was wrong. And you never know when/if it might happen again.