Free 7 Day Trial RV GPS App RV Trip Planner Campground Reviews RV Maintenance Free 7 Day Trial ×
 

Go Back   Thor Forums > Thor Tech Forums > Maintenance and Repair
Click Here to Login
Reply
 
Thread Tools Display Modes
 
Old 03-29-2021, 12:24 PM   #1
Junior Member
 
Brand: Thor Motor Coach
Model: Synergy 24MB
State: Pennsylvania
Posts: 15
THOR #16965
Batteries not powering 12V Coach

Hi, I've got a 2019 Thor Synergy and mistakenly drained my AGM batteries to 11.4 volts on a recent trip. After turning the converter back on the batteries returned to full charge, BUT no power to the 12V coach system - e.g. the display that controls the lights, etc. wont power-up AND the steps stopped working. Here's what I've troubleshot so far:
  • When my shore-power or generator is running - all the 12V systems work great.
  • Using my volt-meter I can see a full 12.6V + charge on the batteries and my leveling jacks still work.
  • I substituted my existing batteries with a known fully charged battery, still no 12V to the coach systems or steps
  • The solar charge controller is thowing a code that means either low-voltage or no-battery present
  • No light on the 12V Coach on-off switch (except when running on Shore Power or Generator
  • After studying my circuit diagrams, I suspect it might be the battery disconnect or maybe that 50Amp Type III breaker. Would you agree?
I've tried tracing the battery cables and the wiring on the 12V Coach switch with no success. Where might that battery disconnect switch be located?

__________________
SunriseCamp is offline   Reply With Quote
Old 03-29-2021, 01:53 PM   #2
Site Team
 
16ACE27's Avatar
 
Brand: Thor Motor Coach
Model: ACE 27.1
State: Florida
Posts: 6,421
THOR #7035
"After studying my circuit diagrams, I suspect it might be the battery disconnect or maybe that 50Amp Type III breaker. Would you agree?"

I agree EXCEPT if that was the problem how did the converter charge the batteries? The power from the converter goes through both of those items as well.
__________________
Ted & Melinda
2016 ACE 27.1
2016 Chevy Sonic Toad
2020 Chevy Colorado Z71 Trail Runner Alternate Toad
16ACE27 is offline   Reply With Quote
Old 03-29-2021, 03:45 PM   #3
Senior Member
 
Brand: Thor Motor Coach
Model: Siesta 24SS
State: California
Posts: 1,407
THOR #12698
On the solar battery code issue, does your controller have the option to switch from lead acid batteries to AGM batteries? On my controller I have to switch between them to correctly charge what type of house battery I have installed. You might look around and under your house battery compartment to see if there is another in line fuse that might have gone out. I have a 20 amp in line just under my steps next to the battery compartment.


Paul
__________________
paulwadley is offline   Reply With Quote
Old 03-29-2021, 05:12 PM   #4
Junior Member
 
Brand: Thor Motor Coach
Model: Synergy 24MB
State: Pennsylvania
Posts: 15
THOR #16965
16ACE27, You are right about the Converter not being able to charge the batteries, I must have gotten the re-charge by driving the RV, as the connection to the coach battery is on the same side of the circuit as the house batteries than got drained.
__________________
SunriseCamp is offline   Reply With Quote
Old 03-29-2021, 05:18 PM   #5
Junior Member
 
Brand: Thor Motor Coach
Model: Synergy 24MB
State: Pennsylvania
Posts: 15
THOR #16965
paulwadley, yes - the solar charge controller is configured to support AGM batteries. I do have a 12V breaker directly under the steps, but assumed it was the breaker for the steps. I'll try swapping it out to see if that fixes my issue. The wiring from the solar charge controller and the disconnect switch both head toward the back of the RV where the converter et. al. is located. I don't know what the batter disconnect looks like or if it's got a reset switch I can just push....
__________________
SunriseCamp is offline   Reply With Quote
Old 05-08-2021, 10:32 PM   #6
Junior Member
 
Brand: Thor Motor Coach
Model: Synergy 24MB
State: Pennsylvania
Posts: 15
THOR #16965
My problem was solved - there was a bad 50 Amp breaker located next to the Solenoid that switches the 12V house system on/off. Very difficult to reach as it was behind the converter / AC breaker panel.
__________________
SunriseCamp is offline   Reply With Quote
Old 06-08-2021, 09:12 PM   #7
Senior Member
 
Brand: Thor Motor Coach
Model: '17-Vegas 24.1
State: California
Posts: 1,594
THOR #13362
Just an FYI...
I had a similar problem but a different fix.

I had no power in coach except with genny on (I was boondocking)

After much diagnosis...
I realized the solenoid in the Use/Store mechanism went bad
The switch at the door made a clicking sound at the solenoid so I assumed that the solenoid was fine.
But I couldn’t get any DC in the coach unless the genny was running.

So I connected the two positive cables together at the solenoid
And now everything in the coach works fine (except I have no UseStore switch)

By connecting the cables together is like not having a Use/Store solenoid.


In your case...how did you determine that the 50amp breaker was bad?
Mine doesn’t have a “flag” or indicator on it that it’s tripped or blown.
__________________
'17 Vegas 24.1
Fallbrook, CA
taylorbob1 is offline   Reply With Quote
Reply

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


» Featured Campgrounds

Reviews provided by

Disclaimer:

This website is not affiliated with or endorsed by Thor Industries or any of its affiliates. This is an independent, unofficial site.




All times are GMT. The time now is 08:46 PM.


Powered by vBulletin® Version 3.8.8
Copyright ©2000 - 2021, vBulletin Solutions, Inc.
Content Relevant URLs by vBSEO 3.6.0 PL2