Marty57

Success! I purchased a 45 watt converter kit that was a direct replacement for the OEM converter. Install was pretty easy, everything included. The kid came with a new fuse panel. The system will now trickle charge the battery after it quickly brings it back up when discharged. Also, all the systems will work with or with out a battery installed. All's good. I attached a shot of the new unit in place before closing it up and a picture of the box with the unit info. At less that $200 I think I came out ok. Thanks for all the help. Marty

I agree with your analysis. I found the owner's manual for the unit I have and a trouble shooting guide. The convertor is definitely bad. The manufacturer makes a direct replacement upgrade kit for the unit I have. Here's the link: http://www.bestconverter.com/45-Amp-Converter-Replacement-Kit_p_46.html#.V5AmTY40dgF The site shows how to change out the unit and the pictures exactly match what I have. I do want to stick with the same size unit, their isn't any room for a larger battery in the engine compartment. I think it's time to order a new convertor. I feel pretty comfortable installing the new unit, not much to it. As to the fuse sizes and the burning, that has been like that a long time so not sure if it's related to the failure or not. The burnt area is a 15a for lights, and the small 5 amp is for the water heater controls. The replacement kit comes with a new fuse panel and the new controller so everything gets replaced. Sounds like an easy repair to me. Any known issues with this replacement unit? If not, I think it's time to order the new unit. Marty

First, the fridge. It is not a 12V fridge; only 110v or Propane. The 12v just runs the electronics. My system has a 45a Converter with battery charger (see pictures below). First picture is the label, followed by the inside of the converter than inside fuse panel and last the fuses. I took a bunch of voltage measurements and got some very strange readings unless I have no idea how this should work. Looking at the fuses, voltage from the white lug to fuses (L to R) 1-6 was 12.8v. Fuses 7-9 read 3.36V. Fuse #8 is the charging circuit to the house battery according to the label on the panel. Next, from the red lug to the fuses: 1-6 all measured 9.48V; 7-9 0 V. Next, the upper blue wire screwed to the top center of the fuse panel. Fuses 1-6 read 0 V; 7-9 read 9.3V. Measuring voltage across the three lugs also gave similar voltages: White to Blue lug 12.8V. Red to Blue lug 9.1V. Red to White lug 3.6V. Something seems really incorrect with these readings unless I don't understand how this should be working. When I check voltage at the house battery terminals I get 3.3v, about the same as at the fuse. With these readings and the pictures anyone care to venture a diagnosis? Seems to me the converter isn't working correctly; I don't understand the different voltages at the fuses but something seems to not be working correctly. Ideas? Thanks, Marty

My fuse panel is located under the sink, outside the bathroom. I'll pull the cover and have a look. Any way to check the output of the convertor? It's putting out 12v, lights all work. I'm assuming the pump and refrigerator are a higher amp draw and maybe it cant handle the load? The refrigerator is not three way, only 110V or propane; the 12v just runs the electronics as I understand it. Thanks. Marty

If it is the converter, where is it mounted? Is it in the panel behind the house type breakers in the coach? I did order a new isolator but I'm thinking also that it's working ok. I bought a new 40A breaker to replace the one I have even though it checks out ok. The two 6A seem to work ok, I wanted to change them out but I am having trouble finding a 6A 12v breaker with plastic tabs as installed. How can I check the convertor? I sure appreciate all the help, I'll try a few of the things above after I put things back together. Marty

Here's a couple pictures of the circuit breakers and the isolator. The isolator has a diode in the line; removed and checked and it's ok. Soi far, everything checks out. Ready to replace circuit breakers and isolator even though they check out. Marty

I discovered the problem just recently. I had been away from the motor home for a couple weeks and the motor home was plugged into shore power as usual. I use the restroom in the motor home when I'm working in the yard, that's when I found that the water pump was not working as it usually did. When I brought the battery in to Sears to have checked, it required a 45 minute charge to bring it up to power. This led me to do some digging. This is how I discovered that the shore power is no longer charging the battery and will not supply power to the pump and refrigerator even though all other appliances and lights work without the house battery connected and with the vehicle connected to shore power. I've had this motor home for over ten years and the shore power has always provided the necessary power and kept the batteries charged until now. This is why I'm stumped. I just finished taking apart the wiring block that has the isolator relay mounted on it. There is a 12V 40A circuit breaker with a re-set button on the side and two 12v 6A circuit breakers with out re-set buttons. When I check them with an ohm meter they read 0 ohms of resistance, showing they are not open and allow current to flow. I'm not sure how to check the isolator. I am going to replace the circuit breakers and the isolator on the off chance that they are some how causing the issues. There are also a couple if splices in wires leading into the circuit breakers that I will check out first. I think you can see why this is so difficult to trouble shoot and why I'm looking for any and all suggestions as to how to proceed. No need to pay over $100/hour for some of the diagnostic work if I can eliminate some of the issues first. Time to check out the splices and replace the circuit breakers. Marty

Here's some more info based on your ideas and questions above. Below is a picture of the circuit breaker type mounted above the isolator. They are the reset type with a rectangular button on the side. I can only get to the top one and the button moves in and out with no determinable detente or stop I need to pull the battery to get a better look. The battery (distilled water is up on all cells) reads about 12.5 volts; Sears charged it and did a load test and said it was in good shape. The pump and refrigerator works fine on the house battery when charged; the fault is only when on shore power without the house battery connected. On shore power, there is only 2.5-3V reading at the battery terminals for the house battery with the battery disconnected. All systems come on line correctly when I turn on the ignition with the house battery disconnected. With the house battery disconnected and the button connecting the two batteries together held down, the pump still does not work. Regarding a wiring diagram, no I don't have one. The motor home is a 93 Tioga Arrow, 25' long. I'll pull the battery and remove and check the breakers. The isolator and breakers would be fairly easy and cheap to replace but I don't like just replacing parts shot gun style with out knowing the problem. I'll see how these check out today. Thanks for the help, pass along any other ideas you may all have and I'll check them out. Marty

I did a little checking and it looks like I have a relay based isolator. It looks like the one I attached here. I did a little testing of the isolator. With the chassis battery disconnected and the house battery in place, there is no power to the starter. When I press the button to connect the two batteries the engine turns over and the starter engages, starting the engine. So I know it functions in that test. There are three or four circuit breakers attached above the isolator. Could the isolator or one of these circuit breakers cause the symptoms I have found? How can I check the circuit breakers and the isolator? Thanks Marty

Th battery was my first thought. It's only 15 months old. I returned it to Sears to be checked out. They gave it a clean bill of health. As for an isolator, I have no idea what I have or even what to look for. I'm not familiar with an isolator in the circuit so not sure what to look for. Still stumped but thanks. Marty

I'm new to the forum but not to RV's. Been at this for 30+ years but am stumped by this problem. I have a '93 Tioga Arrow that I have owned for about ten years so I know it pretty well. Recent problem has come up with the 12V charging system to the house battery. My battery ran down and I suspected it was the battery but it checked out OK. Everything works with engine running or with generator running. If house battery is fully charged (from outside source) everything works. Shore power works until I disconnect the house battery. At that point, the water pump and the refrigerator (Gas/AC type) no longer function but everything else continues to work. When I disconnect the house battery and am hooked up to shore power, I get only about 3V at the connection for the house battery. Pulling out a bulb inside motor home with shore power plugged in and house battery disconnected, I get about 12.5V. Over time, the house battery seems to go down and the shore power will not charge it even though shore power provided power to the lights and range hood, just the refrigerator and water pump are dead. With house battery disconnected I can start the engine and everything works, including the refrigerator and the water pump. To recap, refrigerator and water pump will not work on shore power alone. Any ideas? I'm baffled. I checked all the fuses and they are all good. There are a series of relays and a solenoid bolted to a heavy piece of steel than that steel is bolted to the chassis; I removed and cleaned up the surfaces to insure good ground and no change. Any ideas of what this might be or how to trouble shoot this sure would be appreciated. Thanks, Marty