New Windsport 34J Owner...with issues!

[Judge]

Originally Posted by RACarvalho

It may be that the house batteries BMS is shutting down the batteries to preserve them because they are very low SOC.
Try to charge the batteries with an external charger and see if everything gets back to normal.
If it gets back to normal, then you need to figure out why the batteries are not being charged by the engine alternator when driving.... Possibly a problem with the Li-BIM (wrong connection or faulty unit) as stated above.

Fair point about the BMS and that could be an issue down at 12.6V. I'd be surprised if the BMS was shutting down the batteries when he was at 13V... unless there was some other issue as well.

The OP also wants to be careful about using just any battery charger. I suspect he doesn't have an LI compatible charger if these are his first LiFePO4's. If he has a charger that has an AGM mode, he could get away with it.

That is why I suggested running the engine and then measuring voltage to verify the BIM operation. If it is working properly, he can drive the coach around to charge them.... if his generator is no doing it.

[RACarvalho]

Originally Posted by Judge

The OP wants to be careful about using just any battery charger. I suspect he doesn't have an LI compatible charger if these are his first LiFePO4's. If he has a charger that has an AGM mode, he could get away with it.

That is why I suggested running the engine and then measuring voltage to verify the BIM operation. If it is working properly, he can drive the coach around to charge them.... if his generator is no doing it.

I'm guessing the BMS also controls the charging process (?)

[Judge]

Originally Posted by RACarvalho

I'm guessing the BMS also controls the charging process (?)

The BMS will protect against over-voltage or under voltage and keep the cells balanced at the top of the charging cycle by changing the charging rate for each cell as needed until 100%.

So theoretically if the charger he uses is not LI compatible and falls outside the BMS parameters, it should protect the batteries if it detects an unacceptable charging condition. I'm just a little anal about using the right components in the off chance the BMS doesn't do its job and damages a battery given the cost.

[RACarvalho]

Originally Posted by Judge

The BMS will protect against over-voltage or under voltage and keep the cells balanced at the top of the charging cycle by changing the charging rate for each cell as needed until 100%.

So theoretically if the charger he uses is not LI compatible and falls outside the BMS parameters, it should protect the batteries if it detects an unacceptable charging condition. I'm just a little anal about using the right components in the off chance the BMS doesn't do its job and damages a battery given the cost.

So it may be that, if he doesn't have a DC-DC converter/charger to charge the house batteries from the engine alternator, his alternator is sending energy outside of BMS parameters and the BMS is not allowing the charging to take place (?).
In this case it would make sense that the batteries are not being charged when on the road and would eventually reach the point where the BMS shuts everything down to preserve the batteries and are being charged by the converter(which sends the right voltage/current) when on shore power...
It may be that it was always this way but previous owner never took a long road trip (?) or maybe a faulty BMS or alternator could cause that (?)

[Judge]

Originally Posted by RACarvalho

So it may be that, if he doesn't have a DC-DC converter/charger to charge the house batteries from the engine alternator, his alternator is sending energy outside of BMS parameters and the BMS is not allowing the charging to take place (?).
In this case it would make sense that the batteries are not being charged when on the road and would eventually reach the point where the BMS shuts everything down to preserve the batteries and are being charged by the converter(which sends the right voltage/current) when on shore power...
It may be that it was always this way but previous owner never took a long road trip (?) or maybe a faulty BMS or alternator could cause that (?)

There is an LI-BIM225 installed that is designed to charge Lithium batteries from the alternator. If it is wired properly, the house batteries would be charging from the alternator.

According to the OP, the batteries were only reading 12.6V when the generator was running. That would mean the Converter was not charging. We are waiting for him t update us after the generator ran several hours.

If the BMS is in protection mode, I’m not sure what the battery voltage would read…. If anything.

[cgani93]

Originally Posted by Judge

A coupe of points.....

1) 13V for LiFePO4 batteries is 30% DoD assuming no load on them at all. That is starting to get pretty low but still plenty of power to power a radio. The Levelers probably would not likely give a Low Voltage Alarm either (I'm assuming that is the beeping he hears when the LCI panel lights up) because the alarm voltage is generally configured for lead acid batteries and 13V would even be considered a full charge for AGM batteries.

2) The LI-BIM225 will be charging the house batteries when driving. All of his problems started while he was driving. We don't know what the voltage was while he was driving and the problem started.

3) In terms of shore power, we don't know if the original owner installed an Inverter / Charger instead of upgrading the Converter for the LiFePO4's. We don't know at this point whether the LiFePO4's have the right charging mechanism for shore power. We do know the original owner at least upgrade the BIM to the LI-BIM.

4) When his batteries got down to 12.6V, he is at about 15% DoD. Still enough power for the radio.

5) When the Emergency Start button was pressed, it manually enabled the BIM relay to connect the chassis batteries to the house batteries and this added additional power. If this gave him enough power to start the generator, then that would point to a battery power issue, which does contradict some of my earlier points.

6) If the generator was running for a while and he was only seeing 12.6V, that would mean the Converter / Charger (or Inverter / Charger) is not charging the house batteries. Could be the Use / Store switch and circuit or could be something else.

7) Many a BIM have been incorrectly wired by Thor at the factory. We don't know if the original owner verified that his BIM was wired correctly by Thor when he upgraded to the LI-BIM. If it was not wired correctly and he just did a wire swap, that could mean the BIM is not wired properly and that can cause a whole bunch of electrical issues like the OP is seeing (I am speaking from personal experience). The fact that his issues started while driving makes me start to suspect the BIM wiring.



To the OP.......


1) You said you disconnected the MH battery. Do you mean you disconnected the chassis battery (engine starting battery) or you disconnected the Lithium Batteries?

2) You said it was an aftermarket Radio / GPS and it went out during the drive home. Did the original owner wire it to the house batteries and not the chassis battery? I would have wired it to the chassis battery but I'm assuming it was wired to the LIFePO4's / house batteries. Because if it was a battery power problem and it was wired to the chassis battery, then you would have issues with the motorhome itself i.e starting issues, etc.

3) Have you started the motorhome and then checked the voltage of the LiFePO4's while it was running? Right now this is the most important step you should do if running the generator did not charge your batteries and solve your problem!

If not, start the motorhome and put a meter on the house batteries. After a few minutes you should see the voltage jump to 14V once the BIM analyzes the chassis battery voltage and the house battery voltage, it would kick in so the alternator starts charging the house batteries.

If you do see 14V at the house batteries, let the engine run a while to boost the charge of the house batteries and then see if you get power back. This also means the batteries should have been charging on the drive home and "dead" batteries would likely not have been the cause of this issue.

After the engine has run for a while and brought up the charge to the house batteries, see if you get power to start the generator, use the levelers, etc.

If you don't get charge power to start the generator or use the levelers and / or the radio doesn't work after running the engine a while, try holding the Emergency Start button and see what happens then.

If you are not seeing 14V at the house batteries after starting the motorhome and waiting a couple minutes so the alternator can start charging them, then your BIM could very well be wired incorrectly and causing some, if not all, of your issues.

4) Do you have a residential fridge and is the Inverter on? If so, this is draining power from your house batteries. Unless you plug into shore power, have solar, run the generator or run the engine, you are going to fully deplete the house batteries and that does not help with troubleshooting. Empty the fridge and turn the Inverter off.

If you have a residential fridge and it was on during the drive home, it would have been draining the house batteries. Then if the BIM was wired incorrectly, your house batteries would not have been charging properly by the alternator and your house batteries would be discharging the entire drive. The combination of these two possibilities would have caused your issues on the drive home.

This was actually the first sign something was wrong with the charging circuit in my 2020 Magnitude. After having my house batteries lose power while driving with the fridge running several times, I did a bunch of troubleshooting. I was able to determine that Thor wired the BIM incorrectly and once I rewired it, all of my problems were corrected. Many other owners with similar issues found the same root cause.

The answers to your questions in order.
1. Yes, the chassis battery not the house batteries. They haven't been disconnected at all.
2. Appears to be wired to the house batteries. I agree.
3. Yes - the house batteries were charging yesterday on the generator for about 3-4 hours however they never reached above 13.7V's. Today when I opened the coach after it sat for about 12 hours, the meter read 12.3V's which feels low for a coach just parked for 12 hours. We started the generator this morning without issue and the house batteries appear to be back at 13.7V's but no higher. I haven't started the coach motor today but I will later today to verify if the house batteries see 14V's. (Also of note, there seems to be a difference of about 0.5 volts between the meter on the inside of the door and the display screen in the coach)
4. Fridge was turned off the whole drive, I shut it down prior to departure so it wasn't that that drained the batteries. My thought after all of this is that the motorhome's alternator isn't charging the house batteries, but the generator is.

[Judge]

Originally Posted by cgani93

The answers to your questions in order.
1. Yes, the chassis battery not the house batteries. They haven't been disconnected at all.
2. Appears to be wired to the house batteries. I agree.
3. Yes - the house batteries were charging yesterday on the generator for about 3-4 hours however they never reached above 13.7V's. Today when I opened the coach after it sat for about 12 hours, the meter read 12.3V's which feels low for a coach just parked for 12 hours. We started the generator this morning without issue and the house batteries appear to be back at 13.7V's but no higher. I haven't started the coach motor today but I will later today to verify if the house batteries see 14V's. (Also of note, there seems to be a difference of about 0.5 volts between the meter on the inside of the door and the display screen in the coach)
4. Fridge was turned off the whole drive, I shut it down prior to departure so it wasn't that that drained the batteries. My thought after all of this is that the motorhome's alternator isn't charging the house batteries, but the generator is.

Even though the fridge is off, is your Inverter on? If so, lets get that turned off for now.

The difference in 0.5V reading from the meter to the display can be because of a voltage drop. Thor is not very good about making sure proper wiring is used to minimize voltage drops.

If your batteries are deeply discharged it could take much longer than 3 - 4 hours to get the charge up depending on the rating of the Converter Charger (60A, 80A, etc.).

If your generator started without using the Emergency Start button, then that means the batteries did start charging. Now you should be seeing over 14V when charging and ~13.6V if the Converter / Charger has a Lithium Second Stage Charging capability after the batteries are fully charged (the Progressive Dynamics PD9160ALV Converter has this capability as well as high-end Inverter / Chargers).

What about your levelers and radio? Are they working again now that the generator starts on its own?

If your BIM is wired incorrectly, then it will wreak havoc on proper charging. You want to perform the test I gave you with the engine running to make sure the BIM is working properly but you can verify that the chassis battery cable is going to the left post on the BIM marked Batt Chassis. There should also be a second small wire on that post as well. That provides the chassis battery voltage reading on your display.

Then you should verify the house batteries are connected to the post marked Batt Coach. There should be no other wires on that post.

[Judge]

Here is another test for making sure your BIM is wired and working properly:

1) Note the Chassis and House Battery Voltages first using a good multimeter.

Part One

2) Plug into shore power (engine should not be running) so that Converter Charger or Inverter Charger has power.

3) Turn on the coach headlights to start draining the chassis (engine starting) battery.

4) When the Chassis battery drops to ~12.5V and you should hear the BIM relay kick in and the chassis battery voltage should then go up to 13.5V minimum as the Converter / Charger or Inverter / Charger starts charging the chassis batteries while on shore power.

Part Two

5) Turn off coach headlights and unplug the shore power.

6) Start the engine.

7) Start draining the house batteries by having the Inverter on and the fridge on, TV on, lights on, furnace on, etc.

8) When the LiFePO4 house battery voltage drops down to ~13.3V you should you should hear the BIM relay kick in (as long as the chassis batteries are up to 13.4V minimum). The chassis batteries have to be at the proper voltage before the BIM will allow the house batteries to start charging. When the BIM relay kicks in, you should then see the house battery voltage increase to ~14V indicating that the alternator is charging the house batteries while the engine is running.

If all that happens, your BIM is wired properly and is working as it should. If not, then you need to look at the wiring per my previous post.

[cgani93]

Originally Posted by Judge

Here is another test for making sure your BIM is wired and working properly:

1) Note the Chassis and House Battery Voltages first using a good multimeter.

Part One

2) Plug into shore power (engine should not be running) so that Converter Charger or Inverter Charger has power.

3) Turn on the coach headlights to start draining the chassis (engine starting) battery.

4) When the Chassis battery drops to ~12.5V and you should hear the BIM relay kick in and the chassis battery voltage should then go up to 13.5V minimum as the Converter / Charger or Inverter / Charger starts charging the chassis batteries while on shore power.

Part Two

5) Turn off coach headlights and unplug the shore power.

6) Start the engine.

7) Start draining the house batteries by having the Inverter on and the fridge on, TV on, lights on, furnace on, etc.

8) When the LiFePO4 house battery voltage drops down to ~13.3V you should you should hear the BIM relay kick in (as long as the chassis batteries are up to 13.4V minimum). The chassis batteries have to be at the proper voltage before the BIM will allow the house batteries to start charging. When the BIM relay kicks in, you should then see the house battery voltage increase to ~14V indicating that the alternator is charging the house batteries while the engine is running.

If all that happens, your BIM is wired properly and is working as it should. If not, then you need to look at the wiring per my previous post.

Got it. Tracking on all of this. Huge help my friend...thank you.

[Geronimo73]

We have a ‘17 34J bought new. There’s a “store/use” switch near the entry way that we have, more than once, accidentally tapped while moving stuff in & out. While in store use, you’ll get no power to the house, including the backup cam & radio controls. Click “use” and se if that helps.
Our leveling system will occasionally mysteriously turn on and blink & make noise while driving. I wait till the next stop and try resetting the system - usually works.
Hope this helps!

[Geronimo73]

Oh and as far as traveling in this model during red flag cross winds? White knuckles my friend, white knuckles. I intend to upgrade my suspension with the appropriate upgrades to help in this space.

[cgani93]

Originally Posted by Geronimo73

Oh and as far as traveling in this model during red flag cross winds? White knuckles my friend, white knuckles. I intend to upgrade my suspension with the appropriate upgrades to help in this space.

Don't I know it! The coach has upgraded springs and the roadmaster sway bar so that helped for sure, but I describe the journey like I'm wrestling an invisible tiger for 17 hours. Feels about right.