Battery drain while towing

[sweese]

I have a 2018 flying cloud 27 with a problem I cannot figure out. My batteries drain when not connected to shore power and I am not sure what is drawing the current.

While towing settings are:

1. Store/In use setting set to "In use"
2. Furnace off
3. Water Pump off
4. All interior lights and fans off
5. Frig on (LP)

on two subsequent 450 mile (8 hour) jaunts my batteries went down to 9v. Trailer lights never dimmed so all seems ok with the connection to my truck a RAM 2500. Has anybody encountered this? Is it possible there is a short? I doubt the frig is taking much 12v while on LP.

[azflycaster]

9 volts is dead. Have you let the trailer sit in the same configuration without being hooked to the TV or to shore power to see if the problem is with the trailer?

[sweese]

Originally Posted by azflycaster

9 volts is dead. Have you let the trailer sit in the same configuration without being hooked to the TV or to shore power to see if the problem is with the trailer?

Good call Richard. I always have it hooked up to shore power when at home. I just unhooked it from shore power. "In use" now but everything else is off including the frig. I was 12.9 after I unhooked the shore power and will look at it in a couple of hours.

[uncle_bob]

Hi

Assuming you have flooded batteries, checking them for water would be a really good idea.

Bob

[Paprika]

In addition to what Bob said (e.g., your 24/7 shore-power hookup may have boiled the batteries dry), consider the possibility that the batteries were no good from the start, having been allowed to die as the rig sat on the dealer's lot.

Yes, check the fluid level and refill if necessary... but after draining them to 9 V, I suspect you're going to want to replace them sooner rather than later.

[Bobbo]

Another possibility is that your tow vehicle is not supplying 12v power to the trailer connector for charging the battery, and some phantom draw in the trailer is draining the battery. Get one of these 4 pin/7 pin testers and see if you have 12v at the connector.

https://www.northerntool.com/shop/to...6892_200466892

(I can't get the link to work right. In Northern Tool's search area, search for 4 pin 7 pin tester.)

[sweese]

Originally Posted by Paprika

In addition to what Bob said (e.g., your 24/7 shore-power hookup may have boiled the batteries dry), consider the possibility that the batteries were no good from the start, having been allowed to die as the rig sat on the dealer's lot.

Yes, check the fluid level and refill if necessary... but after draining them to 9 V, I suspect you're going to want to replace them sooner rather than later.

Thanks. I think you are correct and I should have checked them earlier. They were both low and I have refilled. I will charge and do a load test later today but I am not optimistic.

[Hikingsolo]

While towing a SOB this summer I had the same problem. My Tacoma battery charging circuit fuse blew when I accidentally plugged in the old and damaged 7 pin connector upside down. Did it twice! Kept fuses on hand after the first incident. BTW , the Taco has a separate circuit for charging a trailer battery. Wondering if your truck has a similar circuit.

The net result of the blown fuse was that the fridge drew down the battery very quickly.

[wrhnco68]

I had the same issue with my 2001 Safari and my 2006 Chevy Silverado.

My Silverado did not have a fuse in the circuit for the power to the 7 pin connector. It had a red blanking cap instead of a fuse. Replaced it with a fuse. That corrected the "charging while driving" issue.

When parking overnight, I still ran the batteries down more than I felt reasonable. Turns out that I left the I kept leaving my TV booster on. Since it was inside the cabinet under the TV, it was easy to overlook.

Bill

[joebutler]

Originally Posted by sweese

I have a 2018 flying cloud 27 with a problem I cannot figure out. My batteries drain when not connected to shore power and I am not sure what is drawing the current.

While towing settings are:

1. Store/In use setting set to "In use"
2. Furnace off
3. Water Pump off
4. All interior lights and fans off
5. Frig on (LP)

on two subsequent 450 mile (8 hour) jaunts my batteries went down to 9v. Trailer lights never dimmed so all seems ok with the connection to my truck a RAM 2500. Has anybody encountered this? Is it possible there is a short? I doubt the frig is taking much 12v while on LP.

Check your ceiling fan motors and be sure they are totally off. This happened to me and the motors are hard to hear while running. Good luck! AS 25 Limited Classic

[firman]

We had this problem on our first trip out with our 2005 Classic and 2004 F-350. We thought we had a battery problem. A very helpful/knowledgable friend took his test light and found no voltage at the rear electrical plug at the hitch. Turned out we had blown a fuse in the truck for the charging leg of the electrical connection.


We were never able to find out what caused the fuse to blow, but once every year or so we would not be charging our batteries while towing. We would check the 20 or 30 amp fuse for the charging circuit, and it was blown.


Best solution was to find the source of the problem - but apparently it was a transient problem, that occurred occasionally. Next best solution was to plan on using 1 or 2 20 amp fuses per year when the problem occurred.

[joebutler]

Originally Posted by sweese

I have a 2018 flying cloud 27 with a problem I cannot figure out. My batteries drain when not connected to shore power and I am not sure what is drawing the current.

While towing settings are:

1. Store/In use setting set to "In use"
2. Furnace off
3. Water Pump off
4. All interior lights and fans off
5. Frig on (LP)

on two subsequent 450 mile (8 hour) jaunts my batteries went down to 9v. Trailer lights never dimmed so all seems ok with the connection to my truck a RAM 2500. Has anybody encountered this? Is it possible there is a short? I doubt the frig is taking much 12v while on LP.

The electric motor that operates the ceiling fan cover can be stuck on manual and can run the battery down. It is difficult to hear while running. It happened to me.

[uncle_bob]

Hi

The pair of batteries *should* be able to supply 80AH before you get to "stop using" taken to the 9V point it's probably closer to 100AH. If it's real cold out, battery capacity will drop a bit.

The normal fridge pulls about an amp. In an 8 hour drive that's 8AH or about 10% the lower number.

The fantastic fan, unless it's broken, pulls about the same running the deployment motor. (but not the fan it's self). Again, maybe another 10% or so off the battery.

Assuming you are on shore power overnight, the battery *should* be fully charged in the morning with a working charger. Without a working charger, a modern trailer will dump the
batteries dead pretty fast and there is no recovery.

So, to get to a dead battery in 8 hours from full charge, you need something in the 10 to 12 A range for a load. Turning on the inverter and running the TV's is one way to do that. Even running the furnace does not really put on enough load to get into that range.

Flooded cells normally have a "dead space" over the plates. Until they get down to the plates, being low really is not a big deal. If "a little low" is still over the plates - not a problem. If it's 1/3 of the way down on the plates .... not good.

Lots of fun .....

Bob

[scroon]

Originally Posted by uncle_bob

Hi

The pair of batteries *should* be able to supply 80AH before you get to "stop using" taken to the 9V point it's probably closer to 100AH. If it's real cold out, battery capacity will drop a bit.

The normal fridge pulls about an amp. In an 8 hour drive that's 8AH or about 10% the lower number.

The fantastic fan, unless it's broken, pulls about the same running the deployment motor. (but not the fan it's self). Again, maybe another 10% or so off the battery.

Assuming you are on shore power overnight, the battery *should* be fully charged in the morning with a working charger. Without a working charger, a modern trailer will dump the
batteries dead pretty fast and there is no recovery.

So, to get to a dead battery in 8 hours from full charge, you need something in the 10 to 12 A range for a load. Turning on the inverter and running the TV's is one way to do that. Even running the furnace does not really put on enough load to get into that range.

Flooded cells normally have a "dead space" over the plates. Until they get down to the plates, being low really is not a big deal. If "a little low" is still over the plates - not a problem. If it's 1/3 of the way down on the plates .... not good.

Lots of fun .....

Bob

I had the same problem with a brand new trailer . Found out the batteries had dead cells had them replaced under warranty. Don't leave your batteries hooked to shore power continusely you will fry your batteries. When storing my trailer I hook to shore power one day per week then disconnect for 6 days and repeat seems to work for me I never let them drop below 12.1 v

[sweese]

Originally Posted by scroon

I had the same problem with a brand new trailer . Found out the batteries had dead cells had them replaced under warranty. Don't leave your batteries hooked to shore power continusely you will fry your batteries. When storing my trailer I hook to shore power one day per week then disconnect for 6 days and repeat seems to work for me I never let them drop below 12.1 v

After a couple of additional tests, I have confirmed today that the batteries are toast. I plan to take a run at warranty and get them replaced. I appreciate the hint on the shore power. I will limit those connections.

[wulfraat]

Originally Posted by sweese

While towing settings are:



1. Store/In use setting set to "In use"

2. Furnace off

3. Water Pump off

4. All interior lights and fans off

5. Frig on (LP)

Draws include:

- LP gas detector
- Inverter (even when turned off using the remote switch, it will draw current)
- Radio in standby mode
- Fridge even when on LP
- Tank sensors / sea level monitor
- Dometic CCC2 panel / AC control unit

None of this should draw the batteries down too much in 8 hours though.

[Caffeinated]

What kind of charger converter does the 2018 have? If it's a single stage charger boiling the batteries dry is a concern. If AS put in a a multistage charger you should be able to leave it plugged in with no damage to the batteries. Replacing a single stage with a multi stage is a good idea, and terribly expensive.

Mike

[Bobbo]

Originally Posted by wulfraat

Draws include:

- LP gas detector
- Inverter (even when turned off using the remote switch, it will draw current)
- Radio in standby mode
- Fridge even when on LP
- Tank sensors / sea level monitor
- Dometic CCC2 panel / AC control unit

None of this should draw the batteries down too much in 8 hours though.

And, the LP gas detector and the Inverter are phantom draws even if the Battery Use/Store switch is in the STORE position. They are not disconnected. All of the other phantom draws mentioned above are disconnected when in the STORE position.

[daleyocum]

Originally Posted by Caffeinated

What kind of charger converter does the 2018 have? If it's a single stage charger boiling the batteries dry is a concern. If AS put in a a multistage charger you should be able to leave it plugged in with no damage to the batteries. Replacing a single stage with a multi stage is a good idea, and terribly expensive.

Mike

2018 and later FINALLY have a multistage converter.

[uncle_bob]

Hi

Batteries do die and that's just the way things work. The converter chargers that AS has been putting in the modern trailers (like for decades) have nothing to do with it. In the magic speak of converter chargers ... they haven't been "single stage" for a *very* long time.

That's not saying they are perfect or that you can't do better. It's simply saying that they get blamed for things that they very much do not do.

Bob