2023 TELLARO 20L electric issue

[Goin' For Broke]

Hello,

New to the game here. I recently purchased and ran the 2023 Tellaro 20l.
Understanding the electrical system and after trying to diagnose and locate fuses and still not finding a solution I have a list of issues I think that are all interconnected around the charging of the batteries in relationship to when the vehicle is running and or when the vehicle is parked and solar-powered.

I've located the Balmar unit under the bench seat near the electrical panel. No power or lights are on.
MC618

anyone out there have a location of a fuse for this I'm missing or if the unit is in need of replacement

 

[Mark54]

I have the same unit- lucky for you that the MC-618 regulator is mounted to a flat surface so you could find it! Mine was buried on floor...
There is no dedicated fuse for this afaik, mine doesn't have one, unless it's part of the wire that goes to contact #2 or #3 on the diagram below. Trace wires back to see where it originates. I suspect it comes from the front chassis fusebox, or master switch.
My Voltage sense wire (#9, red wire) from battery does have an inline fuse, so check that. Probably underneath with batteries. Attches to B+ battery terminal.
Master switch up front on pass. bed base, or over slider has to be ON for the 2nd alternator, if so equipped, to charge batteries. If that is off, the regulator may be and probably is disabled.
Regulator is supposed to sense low voltage to charge the batteries- can be set with the magnetic reed switch, or Balmar App on phone (easier). It also has a shut off for temperature.
Solar is on all the time- no switch, but there is a fuse as seen in my pic below- the 2023 might have over the slider- mine are behind the bed base end panel. The fuse can be pulled to disable the solar if you work on the electrics.
My Regulator had sensor wires on the wrong terminals as well- #'s 7-8. Black is B-, and red is B+, at least supposed to be... I had to buy a new sensor as original may have been damaged from reverse polarity.
Mine also had a 50A regulator underneath, now up inside, to control the 12V panel feed from the Buss bar- connected to the master switch. See pic below.
Hope this helps- lots to learn.

 

[Goin' For Broke]

Mark,

This is very helpful. I need to crawl under the van and get more involved.

Some isolated control points is when I'm plugged into shore power or a 30amp generator the Van Coach operates as normal. Functions all work. I have noticed GFCI is tripping after charging for a while... this makes me think the LOAD dump once the batteries meet there absorption is not going anywhere.... or is there a load dump?

I bought the van used with 25k miles on it. Pretty clean but I dont think the battery system was taken care off ...

If driving... depending on the batteries and their charge... i can run for maybe a couple hours... tv going and the ac unit running.

Got some order of operations to follow tracing all these wires down.

I dont think I getting solar charging to batteries.... the BM system is showing me inputs. The Balmar gauge is showing SOC AND SOH.... but the readings are all ove the place.

I was able to download the THOR OWENER schematics and get some better ideas of wiring layouts.

Here's my breakdown

Figure out if the 2nd alternator is charging the batteries... I haven't seen this go up in amps whole driving unless I juice it with it emergency start button... it doesn't get them back to the amps needed for the override of mastervolt settings

Other issues is I'm TURNING OFF the masterswitch... yet power still remains ON! (sometimes it turns off everything) This leads me to think the master switch is bad or the shunt or solenoid is faulty.

I can't find the SOLAR CONTROLLER.... THE ONLY place I haven't opened up is the behind the fridge and microwave. Trying to get it parked and let the sun solar keep it charged while it sits 2 weeks at a time .

Ive ordered some back ups as I try to track down the functions.

fuses. BM 618. A controller. Alternator protector. BALMAR stuff.

I seem be happy figuring things out and fixing things or upgrades. Ive got a house boat 95 GIBSON SPORT 37. THEY DID THINGS A LOT SIMPLER BACK THEN!

I built a 8x20 cargo trailer into a tiny house off grid sleeper. 12v system and 120v. Generator and tankless propane hot water and stove and refrigerator. Fresh Water 70g with 80g grey and 45 gallon black tank.Fun project for my jobsite and remote home builds home away from home. Im a general contractor home builder. Love the struggle of logistics!

Will circle back in a week with my findings.

I bought this Austin Texas store it under the sun. I live in Seattle. Traveling 2 weekends a month to visit my daughters!

Thank you so much.

Ryan
3607704000

 

[Mark54]

Mark,

This is very helpful. I need to crawl under the van and get more involved.

Some isolated control points is when I'm plugged into shore power or a 30amp generator the Van Coach operates as normal. Functions all work. I have noticed GFCI is tripping after charging for a while... this makes me think the LOAD dump once the batteries meet there absorption is not going anywhere.... or is there a load dump?

I bought the van used with 25k miles on it. Pretty clean but I dont think the battery system was taken care off ...

If driving... depending on the batteries and their charge... i can run for maybe a couple hours... tv going and the ac unit running.

Got some order of operations to follow tracing all these wires down.

I dont think I getting solar charging to batteries.... the BM system is showing me inputs. The Balmar gauge is showing SOC AND SOH.... but the readings are all ove the place.

I was able to download the THOR OWENER schematics and get some better ideas of wiring layouts.

Here's my breakdown

Figure out if the 2nd alternator is charging the batteries... I haven't seen this go up in amps whole driving unless I juice it with it emergency start button... it doesn't get them back to the amps needed for the override of mastervolt settings

Other issues is I'm TURNING OFF the masterswitch... yet power still remains ON! (sometimes it turns off everything) This leads me to think the master switch is bad or the shunt or solenoid is faulty.

I can't find the SOLAR CONTROLLER.... THE ONLY place I haven't opened up is the behind the fridge and microwave. Trying to get it parked and let the sun solar keep it charged while it sits 2 weeks at a time .

Ive ordered some back ups as I try to track down the functions.

fuses. BM 618. A controller. Alternator protector. BALMAR stuff.

I seem be happy figuring things out and fixing things or upgrades. Ive got a house boat 95 GIBSON SPORT 37. THEY DID THINGS A LOT SIMPLER BACK THEN!

I built a 8x20 cargo trailer into a tiny house off grid sleeper. 12v system and 120v. Generator and tankless propane hot water and stove and refrigerator. Fresh Water 70g with 80g grey and 45 gallon black tank.Fun project for my jobsite and remote home builds home away from home. Im a general contractor home builder. Love the struggle of logistics!

Will circle back in a week with my findings.

I bought this Austin Texas store it under the sun. I live in Seattle. Traveling 2 weekends a month to visit my daughters!

Thank you so much.

Ryan
3607704000

Def. get the SG200 Balmar gateway, and install Balmar app. Then you can see when engine is on, if your UHG is charging or not. Balmar gauge is 'sorta' reliable, but the app is better.
I also have a Victron app for my new solar setup.

Sounds like you know what you're doing if you built a TT tiny house!
Master switch has to be ON for UHG to charge, and for 12V devices to operate.
If 12V power is still on with that OFF, then "something's out askew on treadle" as it were. Bad switch possibly. Trace wiring back to the 50A breaker (underneath). All those components are up inside now in my 20L.

Most RV's and house GFCI circuits are incompatible- trip all the time, so I have a TT30 outlet w/o GFCI for shore power installed in my solar canopy, and use a surge protector on it. I have a disconnect on it too, so I have that off when plugging in, and on when plugged in. You'll never see 30A GFCI at any campground for that matter, just a 20A one for other devices.
Any guests I have, try using my 20A exterior house outlet and trip the GFCI all the time.
RVs are not 'bonded' is why, I suspect.

Same cargo box I have too...! I suggest moving the chairs onto this? (add-on for lid of box)

https://www.stowaway2.com/optional-max-carrier-lid-rack

Solar controller can be well hidden- my Quebec buddy's (Travato I think) was in the back under the rear bed. He had a GoPower 10A PWM unit. The 20K and 20A might be back there too.

My 20L was a 30A PWM (black module) up front in plain view, on end of pass. bed cabinet, but I replaced with a Victron 30A MPPT unit, and added a 'door' to access tank drain. I added two Blue sea breakers to shut down solar as needed/storage, and a Victron guage for solar readouts. make sure your batteries are first on, last off, with the solar controller.
Biggest benefit is access to that tank drain!! I can get BOTH hands on it now.
3rd pic shows before. Impossible to get at that drain valve!!
I can also access the 5A Balmar fuse, needed to reset if Balmar gauge if flashing. Maybe a switch someday...

PS- That Thule XT-2 rack is probably not glued as per manual- and also rated for 130 lbs. So if that generator is heavier- better get that down! At the very least- remount the XT2 carrier with Sikaflex 252 adhesive. Betcha Thor did not glue it... expect lots of paint scratches. End pads not on mine either!

 

[CY20L]

I will say listen to this guy- one smart dude! Helped me figure things out to a T. Shot out to Mak54

 

[Goin' For Broke]

Def. get the SG200 Balmar gateway, and install Balmar app. Then you can see when engine is on, if your UHG is charging or not. Balmar gauge is 'sorta' reliable, but the app is better.
I also have a Victron app for my new solar setup.

Sounds like you know what you're doing if you built a TT tiny house!
Master switch has to be ON for UHG to charge, and for 12V devices to operate.
If 12V power is still on with that OFF, then "something's out askew on treadle" as it were. Bad switch possibly. Trace wiring back to the 50A breaker (underneath). All those components are up inside now in my 20L.

Most RV's and house GFCI circuits are incompatible- trip all the time, so I have a TT30 outlet w/o GFCI for shore power installed in my solar canopy, and use a surge protector on it. I have a disconnect on it too, so I have that off when plugging in, and on when plugged in. You'll never see 30A GFCI at any campground for that matter, just a 20A one for other devices.
Any guests I have, try using my 20A exterior house outlet and trip the GFCI all the time.
RVs are not 'bonded' is why, I suspect.

Same cargo box I have too...! I suggest moving the chairs onto this? (add-on for lid of box)

https://www.stowaway2.com/optional-max-carrier-lid-rack

Solar controller can be well hidden- my Quebec buddy's (Travato I think) was in the back under the rear bed. He had a GoPower 10A PWM unit. The 20K and 20A might be back there too.

My 20L was a 30A PWM (black module) up front in plain view, on end of pass. bed cabinet, but I replaced with a Victron 30A MPPT unit, and added a 'door' to access tank drain. I added two Blue sea breakers to shut down solar as needed/storage, and a Victron guage for solar readouts. make sure your batteries are first on, last off, with the solar controller.
Biggest benefit is access to that tank drain!! I can get BOTH hands on it now.
3rd pic shows before. Impossible to get at that drain valve!!
I can also access the 5A Balmar fuse, needed to reset if Balmar gauge if flashing. Maybe a switch someday...

PS- That Thule XT-2 rack is probably not glued as per manual- and also rated for 130 lbs. So if that generator is heavier- better get that down! At the very least- remount the XT2 carrier with Sikaflex 252 adhesive. Betcha Thor did not glue it... expect lots of paint scratches. End pads not on mine either!

Mark,

Had some success today.. until complete shutdown down after taking it for a drive.. currently no power to the coach but power is showing up the inverter with shore power... but nothing works....

I requested the help of a mobile RV mechanic which went very well in diagnosing the following...
All the breakers were checked up by the main disconnect and everything was functional

Crawled underneath the van remove the access panel to find a couple loose wires and a blown 20 amp fuse!

Restoring the 20 amp breaker then allowed the engine alternator secondary alternator to begin feeding power.

Since I've owned and been driving and using the vehicle the digital readout of the Balmar gauage functioned but that's what led me to understand that I wasn't getting charged to the batteries while I was driving

All along the Balmar unit (mc61 showed no digital readouts..... until the technician and I implemented the readouts of power and power out and came to find that the ground was off or properly in place on the unit as well as the temperature sensor gauges was wired in the wrong spot

My trial on error with success we pop the 20 amp breaker again but then was able to diagnose and with all that wiring and fixed up the Balmar mc618 began showing it s digital display.

I signed out the mechanic happily feeling that we had solved the issue and sent him on his way and then I buttoned everything back up

I plugged in the gateway to the smartshunt secondary port trying to then pull it up on the app nothing was popping up on my phone but I could see on the balmar gauge the understood that there was a gateway.

From the gauge I reset it again and verify that it had 200 amp hours of lithium batteries and left everything else as factory default settings which is probably something more I need to understand on the other settings...

I jumped in the vehicle and decided to take it for a drive and found that I was driving and watching the balmarbgauge and conceived at the alternator was then feeding power to the batteries and everything seemed to be in order.... I turned on the AC unit to draw down the load... not too far down the road the AC unit sucked all the power out of the batteries and there wasn't sufficient enough power coming in from the engine alternator and the master volt switch then shut everything down or the Balmar did or however this works...

I fired up the generator and then got power power backup and was generating power as well as driving down the road and then I got to where I stopped at the next spot when inside came back out and all I could smell was some electrical burning and the Baltimore gauge and the mastervolt dead.... unable to restore power at this point in time

I went back through the van again putting it up on blocks check the 20 amp breaker underneath the van check the main breaker underneath of the van used a tester to make sure that the ANL fuse 250 amp was still good
Still no success I plugged in Shore power and I could get the master of volt read out to say it was receiving power and charging the batteries but nothing else came on.. no 12v no 120v

I opened up the other side of the bench seats and could see the inverter was accepting the power looks like the batteries were completely depleted or it was saying it was charging them but nothing was kicking over

Any suggestions?

 

[Mark54]

Mark,

Had some success today.. until complete shutdown down after taking it for a drive.. currently no power to the coach but power is showing up the inverter with shore power... but nothing works....

I requested the help of a mobile RV mechanic which went very well in diagnosing the following...
All the breakers were checked up by the main disconnect and everything was functional

Crawled underneath the van remove the access panel to find a couple loose wires and a blown 20 amp fuse!

Restoring the 20 amp breaker then allowed the engine alternator secondary alternator to begin feeding power.

Since I've owned and been driving and using the vehicle the digital readout of the Balmar gauage functioned but that's what led me to understand that I wasn't getting charged to the batteries while I was driving

All along the Balmar unit (mc61 showed no digital readouts..... until the technician and I implemented the readouts of power and power out and came to find that the ground was off or properly in place on the unit as well as the temperature sensor gauges was wired in the wrong spot

My trial on error with success we pop the 20 amp breaker again but then was able to diagnose and with all that wiring and fixed up the Balmar mc618 began showing it s digital display.

I signed out the mechanic happily feeling that we had solved the issue and sent him on his way and then I buttoned everything back up

I plugged in the gateway to the smartshunt secondary port trying to then pull it up on the app nothing was popping up on my phone but I could see on the balmar gauge the understood that there was a gateway.

From the gauge I reset it again and verify that it had 200 amp hours of lithium batteries and left everything else as factory default settings which is probably something more I need to understand on the other settings...

I jumped in the vehicle and decided to take it for a drive and found that I was driving and watching the balmarbgauge and conceived at the alternator was then feeding power to the batteries and everything seemed to be in order.... I turned on the AC unit to draw down the load... not too far down the road the AC unit sucked all the power out of the batteries and there wasn't sufficient enough power coming in from the engine alternator and the master volt switch then shut everything down or the Balmar did or however this works...

I fired up the generator and then got power power backup and was generating power as well as driving down the road and then I got to where I stopped at the next spot when inside came back out and all I could smell was some electrical burning and the Baltimore gauge and the mastervolt dead.... unable to restore power at this point in time

I went back through the van again putting it up on blocks check the 20 amp breaker underneath the van check the main breaker underneath of the van used a tester to make sure that the ANL fuse 250 amp was still good
Still no success I plugged in Shore power and I could get the master of volt read out to say it was receiving power and charging the batteries but nothing else came on.. no 12v no 120v

I opened up the other side of the bench seats and could see the inverter was accepting the power looks like the batteries were completely depleted or it was saying it was charging them but nothing was kicking over

Any suggestions?

If the batteries are 0% SOC, then will need to "jump start" by holding the s-start switch to give the Coach batteries a 12.6V boost, while plugged into shoreline.

I have never done this yet, and just met another Tellaro owner with dead coach battery- they tried the e-start, using the engine running with UHG, (no shoreline power at campground we were at) and nothing happened, so hopefully there is someone here who has had success- also try searching website, or call Mastervolt about that.