Thor miramar 34.2 house batteries not charging

[Sparcana]

Hi so my xantech xm1000 kept beeping with e02 error and also leveling system kept saying low voltage. I figured out batteries were dead. I replaced batteries with brand new fully charged and everything was perfect. I hit the disconnect switch just inside the door and hear it click off and all lights turn off. I went back the other day to work on unrelated issue and found my house batteries were dead again. It had only been about a week since I replaced batteries. I turned truck on and ran generator for a few hours. Ac units and lights working. I turn truck off and shut generator off and lights instantly turn off. At this point I'm assuming batteries are not charging at all. I did a bit of research and I learned that a couple things might help. 1st is to hard reset the invertor. To do this you just take all power away from invertor for 30 seconds. Problem with this is I think swapping the batteries does this because I had them disconnected for probably 5 minutes. 2nd issue is battery isolator.

This leads to my question. I have no idea what kind I have to replace it. My rv is 100 miles away so its a pain to drive out to see what it is just so I can order a replacement.

Does anybody know what part number I have or what I should order? Im also going to take a volt meter with me next time. Thank you!

 

[PS89]

You need to fully identify your RV including the model year. That stuff evolves over time and getting the information that is applicable to your RV is critical.

Yeah, a multimeter should be kept with the RV. Can't do much except first-level stuff with the RV without a meter and a plan.

Keep in mind that for the house batteries to charge while unattended, you have to be properly plugged into shore power (or have solar active) and the battery disconnect feature must be left in the connected state so power from the converter can get to the batteries.

You'll also need to specifically identity your battery disconnect feature along with any battery isolator (between chassis and coach). The more specific details you can provide, the more focused can be the responses to your questions without playing "20 questions" to drill down details.

 

[16ACE27]

Your new batteries died because you didn't turn off your inverter. The battery disconnect does not disconnect the inverter.
Your batteries did not charge because the battery disconnect is still open as evidenced by the lights going out when the generator was stopped.
The house batteries may have had some charge restored by running the engine. They obviously had enough charge to keep the generator running.

No more knowledge can be imparted without the Year/Make/Model of your RV.

 

[Sparcana]

You need to fully identify your RV including the model year. That stuff evolves over time and getting the information that is applicable to your RV is critical.

Yeah, a multimeter should be kept with the RV. Can't do much except first-level stuff with the RV without a meter and a plan.

Keep in mind that for the house batteries to charge while unattended, you have to be properly plugged into shore power (or have solar active) and the battery disconnect feature must be left in the connected state so power from the converter can get to the batteries.

You'll also need to specifically identity your battery disconnect feature along with any battery isolator (between chassis and coach). The more specific details you can provide, the more focused can be the responses to your questions without playing "20 questions" to drill down details.

It is a 2014. Im not trying to charge them while unattended. I thought I explained i was trying to charge with generator and truck running for an hour. This post is just to ask for part number.

 

[Sparcana]

Your new batteries died because you didn't turn off your inverter. The battery disconnect does not disconnect the inverter.
Your batteries did not charge because the battery disconnect is still open as evidenced by the lights going out when the generator was stopped.
The house batteries may have had some charge restored by running the engine. They obviously had enough charge to keep the generator running.

No more knowledge can be imparted without the Year/Make/Model of your RV.

How does the inverter get power if battery disconnect is in "store" position? Im pretty sure I had the battery disconnect out of storage mode when I was running generator. I forgot year in title. It is a 2014.

 

[16ACE27]

How does the inverter get power if battery disconnect is in "store" position? Im pretty sure I had the battery disconnect out of storage mode when I was running generator. I forgot year in title. It is a 2014.

A 2014 Class A will likely have the battery disconnect relay in a Battery Control Center (BCC) under the hood.

How does the inverter get power if battery disconnect is in "store" position?

The battery disconnect can not handle inverter current but is a 2014 it may not be an OEM inverter installation so all bets are off.

 

[Sparcana]

Shutting off generator.
Battery Tests.

I took some videos trying to figure it out a bit more. The batteries test fine and I think power to the invertor also tests fine but the xantrex display inside still beeps and only shows 11.9v.

 

[16ACE27]

Shutting off generator.
Battery Tests.

I took some videos trying to figure it out a bit more. The batteries test fine and I think power to the invertor also tests fine but the xantrex display inside still beeps and only shows 11.9v.

It appears your batteries are charging in the second video or they were just charged and you are showing a surface charge.
But the second part of that video looks like you are measuring voltage in an ATS still using the DC scale.

You have not cleared anything up.

You seem confused about the AC from SP or Generator and how it produces DC to charge the batteries/

Have you looked at this generic DC electrical distribution diagram?

The connection between the batteries and the generator is only for starting and running the generator - there is no battery charging there.

The generator supplies 120 VAC to the Power Center and Converter. The converter supplies the house DC loads and charges the house batteries IF the USE/STORE switch is in USE, not if it is in STORE.

 

[Sparcana]

Sorry still learning. Ill change tester and do it again. I tested batteries before I opened door and they were reading 13v so I'm fairly sure they are full charged. When I opened door invertor is beeping and showing 11v. I ran generator for a couple hours. Everything dies soon as I turn generator off. Batteries still showed 13v with everything off again. I had the switch in USE position when I turn generator off. I can its in use because it shuts off my dash radio screen.

 

[PS89]

There's nothing in the ATS that needs to be checked, might as well stay out of it for now. If your 12 volt system, excluding inverter, is working normally when the generator is running or you are connected to shore power, the ATS is working correctly.

What is needed is to compare the battery feed voltage measured at the input to the inverter to the inverter's displayed value on its control panel They should be within a couple of tenths of a volt DC when evaluated at the same time.

 

[Sparcana]

The invetor display reads correctly. I can slowly see the batteries die overnight when I was on generator and shore power ( i tried each way for a few hours). I can see them charge back up if I turn truck on. I use meter on the 12v side of the invertor and it either shows nothing (battery dead) or what batteries are at. Never reads more than batteries current charge. I tried on geny and shore. I think invertor is bad.

 

[16ACE27]

I think invertor is bad.

That's a faulty conclusion. Your INVERTER takes your 12 VDC from the battery bank and creates 120 VAC for limited circuits in the MH. If on SP or Generator it should have no work to do.

But your CONVERTER takes 120 VAC from SP or the generator and converts it to 12+ VDC to power DC loads and charge the house battery bank.

I can slowly see the batteries die overnight when I was on generator and shore power ( i tried each way for a few hours). I can see them charge back up if I turn truck on.

You appear to have a disconnect between the CONVERTER output and the battery bank. I assume lights and DC loads work when on SP or generator running? If so the CONVERTER is doing its job.
Then you hav an issue with either the two 40 amp Reverse POlarity fuses in the Power Center,
The Battery Control Center and battery disconnect latching relay, or
The 50 amp DC breaker located near the house batteries.

 

[Sparcana]

Is this xantrex not an inverter and converter? Yea all lights and everything work fine on generator and SP. Soon as i turn them off everything shuts down. Will not run off batteries at all even if they are fully charged. There is a store switch by door. I can tell it does something when i push it because it kills my radio and makes a clicking sound. Its not in store position on any of this testing. My radio stays on when I kill the SP or geny. I think this switch is just for the chassis battery.

I checked all fuses in the fuse panel under the bed and they are fine (I assume this is the Power Center). I only found 1 relay looking switch in battery bay and it seemed fine as well.

 

[PS89]

Is this xantrex not an inverter and converter?

No. The Xantrex PRO XM1000 & XM1800 are single task devices - inverters.

Yea all lights and everything work fine on generator and SP. Soon as i turn them off everything shuts down. Will not run off batteries at all even if they are fully charged.

That tells us you do not have a completed circuit between the converter AND the batteries. That would be the battery disconnect relay (not identified yet), the 50A breaker in the battery compartment, or the cabling.

I checked all fuses in the fuse panel under the bed and they are fine (I assume this is the Power Center). I only found 1 relay looking switch in battery bay and it seemed fine as well.

A fuse in the power center will not cause your set of symptoms. That "relay looking switch" is probably your battery disconnect relay. A photo of it would be helpful in identifying it.

Do you have a multimeter available?

 

[16ACE27]

Is this xantrex not an inverter and converter? Yea all lights and everything work fine on generator and SP. Soon as i turn them off everything shuts down. Will not run off batteries at all even if they are fully charged. There is a store switch by door. I can tell it does something when i push it because it kills my radio and makes a clicking sound. Its not in store position on any of this testing. My radio stays on when I kill the SP or geny. I think this switch is just for the chassis battery.

I checked all fuses in the fuse panel under the bed and they are fine (I assume this is the Power Center). I only found 1 relay looking switch in battery bay and it seemed fine as well.

Everything you just said CONFIRMS what I just said in the post above yours. As PS89 said, your inverter is NOT a combo inverter/converter.
Yes, the Power Center is the box that contains the AC breakers and the DC fuses. The Reverse Polarity fuses would be two large fuses out of line with the rest of the fuses. You MAY have a standalone converter in which case the Reverse Polarity fuses would be integrated into its case. In that case, don't worry about them because if they were blown you would not have any DC power with SP or generator.

If you have a SINGLE USE/STORE switch it is only for the house batteries, not the chassis battery.
You can't use the radio as a troubleshooting aide in a 12 year old RV. There's no telling how it is wired.

You need to:
Locate the BCC under the hood and find the manual for it
Purchase a multimeter and learn how to use it on YouTube University
OR:
Call a mobile RV mechanic.

 

[PS89]

Locate the BCC under the hood and find the manual for it

2014 Miramar didn't use a BCC.

He NEEDS to get HIS schematics from Thor so he can see how HIS motorhome was supposed to be wired. Tip: See page 8 of the schematics.

 

[16ACE27]

2014 Miramar didn't use a BCC.

He NEEDS to get HIS schematics from Thor so he can see how HIS motorhome was supposed to be wired. Tip: See page 8 of the schematics.

My understanding is that on gas Class As Thor changed from BCCs to discrete components (BIRD/Trombetta/Independent latching relay) sometime in the 2015 model year.

 

[PS89]

My understanding is that on gas Class As Thor changed from BCCs to discrete components (BIRD/Trombetta/Independent latching relay) sometime in the 2015 model year.

Schematic that I referenced shows an isolator solenoid, an RVCP relay, and the Bussman fuesbox.

I think '14 was the first year for the Miramar model.

 

[Sparcana]

 

[PS89]

Gotta love it when the "factory" documentation doesn't match what the factory actually did...