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LSVLance's avatar
LSVLance
Explorer
Apr 29, 2015

Electrical gremlins, need pointed in general direction

My business partner just purchased his first RV, a 2005 Monaco Knight DP with 15,000 miles on it. I get to help keep custody of said RV, use it when he's not and work on fixing and keeping it running. Not a bad gig...except I have almost zero clue where to start.

Main issue has to do with starting the generator, and possibly a side issue with the battery cutoff switch near the door. The dealer we bought it from replaced all house batteries and supposedly went through it bow to stern maintaining everything.

Now, the only way we've found to start the generator is to have the chassis engine running, hold the Boost button down, and press the gen start button on the dash. Even then it struggles to start and you must continue holding the boost button down until the gen engine is warmed up and running smooth. Once it's warmed up, it works normal.

The other issue with the battery cutoff switch has all sorts of weird oddities that we have yet to figure out. At times, depending on which switches are where, the 12 volt house circuit will turn completely off when the door closes, other times the entry step will operate when the porch light switch is flipped, and other times...like right now for instance, even with shore power plugged in, there is no interior power anywhere. I had everything working perfectly on shore power, got cocky and unplugged the shore power and now I can't get any power to come on inside the cabin.

I am a pretty good car mechanic and have had my share of boats, but this is my first foray into a traveling house setup. I can't help but think this is somehow all 12 volt ground related. A Monaco rep told my partner to clean the genset cable connections and see if that helps. I've been under the coach and the connections look pretty good, not recently cleaned and not all corroded either. I plan to try that possibly tomorrow night. I'll take a Digital Ohm Meter under there with me and check for things before I start.

What should have power under there...and when? Is the chassis battery used to start the Generator under normal circumstances? Or does it have it's own battery that might be bad? Is there some other safety feature that I'm missing that may be causing my battery cutoff switch issues?

Lastly, I need to figure out a way to get the entry step cover out. I can hear a motor running when the switch is pressed, but it's locked in place and I can't see how to get it out. Read a bit about micro switches being an issue here, but how does one get to said switches to test or bypass them.

Thanks in advance for any help you can give a noob. I'm stoked to finally have a way to travel without wondering where I'm going to lay my head nor eat a meal...but I'm kind of in the deep end here while still learning how to dog paddle. Hopefully with your help I can get the issues straightened out and get to enjoying this beautiful RV.

19 Replies

  • This was the very last picture I took this morning, everything was turned off, shore power plugged in...



    Notice the 0 amps in the lower right corner... What does that amp indication mean?

    Could my convertor not be charging the house batteries when hooked to shore power?
  • When I press the house battery button to test the battery, is it reading 14.82v because it's picking up the inverter currently charging it? Now that I look closer, in the first pic it looks like the charger is putting 46 amps into the battery, then in the next pic it has dropped down to 35 amps (because the battery is picking up a bit of the charge)...am I understanding that correctly as well. The symptoms do mimic the house batteries being dead in certain instances and in the other instances when everything is working, it is probably the inverter powering things from the shore power making me think the batteries are charged up.

    The coach has been hooked to shore power just about the whole time since it was picked up a week ago except for when it was traveling down the road. I'll leave it hooked up and leave it alone for a couple of days. I'll put the DOM on them tonight when I get home.

    Thanks for the help.

    I did get registered at iRV and am checking for an electrical schematic over there now.
  • The pictures depict that your converter is charging the batteries in a depleted condition. This assumes that the metering system in the RV is correct. First thing I would do is plug the RV into shore power and leave it on for a couple of days. You would take your hand held meter and verify (with shore power on) that the house batteries are being charged with a voltage greater than 12.5V. After the charge has completed and the batteries have been at rest for at least 12 hrs., check the batteries again with your meter. If no loads have been applied (or just the parasitic loads of the RV are present), you should have a reading of 12.6 or so.

    After you've completed this, you can try a generator start, using only the house batteries.

    If none of your lights work or are dim, you are not getting any power from the batteries. This could be due to discharged batteries or a selector switch fault. Once you have the batteries fully charged and have good power to the lights and other DC devices, it would confirm the selector switch is in the correct "run" position. Mark it on the switch.

    Keep posting if you are having other problems. Solutions are usually easy and are posted quickly. Good luck.
  • I think it has something to do with that switch as well. Last night, I ended up with no power inside the coach anywhere, same thing this morning (shore power or no shore power, didn't matter where any switches were. This is what the inverter panel looked like this am.



    The only way I could get power inside was to start the chassis engine. after it ran for a bit, this is what the inverter looked like.



    Shore power was plugged into a 15 amp outlet at the time.

    Chassis engine running, shore power plugged in...



    Then shut off the engine and checked battery status...

    House battery



    Chassis battery



    While trying to get power inside, I flipped the battery cut off switch either direction a couple of times and it made no difference. I haven't touched it since I got everything working again (as I want to keep everything working for now lol) and I'm not sure which way it is set currently (up or down, on or off).

    Is the above enough to verify that the brand new house batteries are charged or should I still take a DOM to them to verify?

    Jerry, do you have a link to the iRV monaco forum?

    Thanks,
    Lance
  • Sounds to me like the battery switch for the house batteries is the culprit. This would explain the intermittent cutoff of the house power and the inability to start the gen unless cross connected with the chassis battery.

    Somewhere out there I saw electrical diagrams for all Monacos. You might try cross posting on iRV2's Monaco forum.
  • something strange having to hold boost button, start at the batteries and make sure there new, not some they had laying around, if new charge,, check every cable for tight fit, take ground off chassis clean to bare metal new bolt, don,t ever trust what comes out of a deakers mouth. they don,t know how too tell the whole truth.
  • westend wrote:
    Do you have a hand held meter?

    The first part of this would be to check the batteries and see if they are charged and their viability. If no one knows how the cut off switch works, there is a good possibility that the batteries have been drawn down.

    You need to break this down into stages of diagnosis rather than, "OK, the batteries are good, why does the generator only start when I push this ?"


    I have a hand held DOM and can check the batteries for voltage, but not sure I can check for their viability (would that be like how an auto parts store draws down a car battery to see what cold cranking amps it'll make?).

    When I first put it on shore power here at the house, the inverter panel (pretty sure that is what it is called) was showing "absorbing charge and 14.XX volts". I took this as to mean that the batteries had an almost full charge on them? Correct or no?

    Also, if the boost switch is used for the house batteries to boost the chassis battery...wouldn't the fact that pressing the boost battery gets the Gen to start show the house batteries are good?

    I agree that we have to break the diagnosys down into stages, I'm hoping you all here can help walk a noob through this. Is it better to start the chasing with it on shore power or not on shore power? I have a feeling the dual systems are clouding my view on things a bit.

    No need to go into the details of the purchase, but the rig is here, and it is going to be up to me to figure out how to get it working properly again.

    Back history on the RV is it is a one owner RV, the previous owner used it to live in it while at his second business in another state. While it has low miles on the chassis, the generator has over 600 hours on it. Everything appears to be in really good shape, can't see any easily visual signs of any hankering done to it anywhere and very little wear at all on it.

    I think it has to be something pretty simple, I just need to know where to start figuring out what works...and what doesn't and why.

    Thank you for your help diagnosing this.
  • Somebody's been wankeling with the electrical and after tearing their hair out, they sold the rig. The dealer put in new batteries and prays nightly you'll be back and sign an open ticket to fix it.

    "Just purchased it" implies you can return and scream at the dealer. It's either that or you'd better start eating your Wheaties...
  • Do you have a hand held meter?

    The first part of this would be to check the batteries and see if they are charged and their viability. If no one knows how the cut off switch works, there is a good possibility that the batteries have been drawn down.

    You need to break this down into stages of diagnosis rather than, "OK, the batteries are good, why does the generator only start when I push this ?"

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