Chassis battery drain while plugged in to shore power - UPDATE

[cinbol]

Hello all,

My original post was too old to reply to but it seems we finally have a resolution two seasons later... and after much searching by us and mechanics for a short. We found only one minor issue in that we have an "AUX" switch allowing our dash radio to run from the coach battery and that was in the wrong position and may have been enough to cause the slight drain we were seeing.

We removed the DIE HARD battery! - it seems that our Winnie/Ford just doesn't like the brand. The new R&R battery recommended by our truck mechanic seems to be working fine and she starts on every demand now..... here's hoping it stays that was as we go thru the season this year!

Original post was Spring 2014:

Very strange issue going on with our rig...2005 Sightseer with 3 brand new batteries - 2 house and 1 chassis

We bought all new batteries this spring. Our problems started when we put the fridge on while on shore power via our home post. The fridge get tripping the GFI... through some investigation and help from these forums we determined it was the heater element. Fridge would run fine on Propane. Doing all the due diligence and hard work we finally freed the element, purchased a new one and great no more tripping the GFI...

However our Chassis battery has a mysterious drain. Fully charged, we disconnected the battery to test it - the battery held it's charge for 36 hours with only a .3V drop.

Checked all the connections on all the batteries, cleaned all terminals we could find and reconnected the battery. Left the coach unplugged and watched the battery checking every 12 hours or so....Over a 4 day period voltage drop was .62V - went from 12.30 > 11.68 - had to use MOM to start the rig and get the volts back up (seems FORD doesn't like anything less than 12V)

Plugged in the shore line - .17V drop in 24 hours

We are completely stumped. The house batteries are fine and will hold a charge for the 4 days when we were not plugged in...

Any suggestions on where to look next? We have downloaded the complete wiring diagram book and will actually be near a Winnebago dealer while camping this coming weekend so will be asking them if they have any suggestions but we are just baffled.

Never had any electrical problems prior to this spring - we bought used and have owned the rig for 4 years - starting our 5th season.

Any suggestions are greatly appreciated.... I have been looking thru the various strings but not seeing this problem discussed.

thanks!
Cindi

[Ray,IN]

Test the onboard charger output, at the battery terminals you should measure at least 13.3 VDC if the charger is working.

[YosemiteBobR]

You wrote:
Plugged in the shore line - .17V drop in 24 hours

Are you saying after plugging into shore power, you are still losing voltage from the chassis battery?


I would check the battery isolater, and all cells in your battery.

[cinbol]

Originally Posted by YosemiteBobR

You wrote:
Plugged in the shore line - .17V drop in 24 hours

Are you saying after plugging into shore power, you are still losing voltage from the chassis battery?


I would check the battery isolater, and all cells in your battery.

Yes that WAS the issue. The chassis battery would loose voltage to the point where the engine would not turn over. The change in battery brands seems to have fixed the issue. We found some very small things like the aux radio button left in the wrong position, but didn't seem enough to be causing the dip...it seems the DIE HARD battery was just not worthy and we seem to be doing fine now. Thanks.

[DAJO]

Like your tow vehicle. We have a 34 Tudor.

[ChasA]

Hi Cindi,
Your Sightseer did not come equipped with provisions to charge the chassis battery from shore power. The chassis battery only gets charged by the alternator which means the engine must be running to charge the chassis battery. For about $50, you can get a Trik-L-Start which will take some of the charge from your house batteries and keep the chassis battery charged. There are electrical items in your coach that are constantly drawing some current.
On the subject of battery brand. There are only a few companies that make batteries and your Diehard battery could have been made by any of them. The problem was more than likely due to the age of the battery and how it had been maintained.
There are ways to measure the current draw and determine which items are taking how much current. But the simplest solution is to just install a Trik-L-Start and be done with the problem.

[Monacoach]

Originally Posted by ChasA

Hi Cindi,
Your Sightseer did not come equipped with provisions to charge the chassis battery from shore power. The chassis battery only gets charged by the alternator which means the engine must be running to charge the chassis battery. For about $50, you can get a Trik-L-Start which will take some of the charge from your house batteries and keep the chassis battery charged. There are electrical items in your coach that are constantly drawing some current.
On the subject of battery brand. There are only a few companies that make batteries and your Diehard battery could have been made by any of them. The problem was more than likely due to the age of the battery and how it had been maintained.
There are ways to measure the current draw and determine which items are taking how much current. But the simplest solution is to just install a Trik-L-Start and be done with the problem.

I dont think the age of the battery was the problem as the op stated they were brand new batteries. I also doubt the brand of battery was the culprit more likely that one of the new batteries was defective. Or perhaps the problem still exists but has not reared its ugly head yet. I have had similar drain issues with the chassis batteries and my fix was to use the disconnect switch and to recharge the batteries before tbey got to low. Letting the chassis batteries drain to a point of not being able to turn the starter over, severely shortens the battery life. On the other hand I thought I was properly maintaining our coach batteries and at 2.5 years im buying new ones. I agree the trickle charger is the way to go

[cinbol]

Originally Posted by ChasA

Hi Cindi,
Your Sightseer did not come equipped with provisions to charge the chassis battery from shore power. The chassis battery only gets charged by the alternator which means the engine must be running to charge the chassis battery. For about $50, you can get a Trik-L-Start which will take some of the charge from your house batteries and keep the chassis battery charged. There are electrical items in your coach that are constantly drawing some current.
On the subject of battery brand. There are only a few companies that make batteries and your Diehard battery could have been made by any of them. The problem was more than likely due to the age of the battery and how it had been maintained.
There are ways to measure the current draw and determine which items are taking how much current. But the simplest solution is to just install a Trik-L-Start and be done with the problem.

thanks - we used a portable trickle charge unit for the last two summers whenever we were away from home to keep the chassis battery levels up, but the new battery seems to have resolved the issue.

We are aware of the few companies that produce batteries which is why our mechanic recommended the change - our new battery is from a different manufacturer than the "die hard". - we have had no further issues since we switched in April - the RV starts up every time with no hesitation!

[cinbol]

Originally Posted by Monacoach

I dont think the age of the battery was the problem as the op stated they were brand new batteries. I also doubt the brand of battery was the culprit more likely that one of the new batteries was defective. Or perhaps the problem still exists but has not reared its ugly head yet. I have had similar drain issues with the chassis batteries and my fix was to use the disconnect switch and to recharge the batteries before tbey got to low. Letting the chassis batteries drain to a point of not being able to turn the starter over, severely shortens the battery life. On the other hand I thought I was properly maintaining our coach batteries and at 2.5 years im buying new ones. I agree the trickle charger is the way to go

You are correct - the Die Hard was a brand new battery when these issues started. My understanding is that disconnect switch only shuts off the coach batteries, you will still have a "drain" from those annoying little things that run off the chassis battery such as the dash clock, etc.

As I mentioned in the original post the battery was not "dead" - the charge was just low enough that it would not allow the engine to turnover. We were told by our mechanic that Fords typically don't like anything less than 12.0 charge so when it dipped to 11.58 - no start!

Changing the brand of battery seems to have done the trick - we have been "out" in the unit 3 times already this season and she starts up every time without issue so far.

thanks for your input!
Cindi

[bobmac]

Winnebago usually connects the slides and steps to the chassis batteries and there is an ongoing draw from the stair controls. Likewise, there is also considerable draw from the engine computer. On my previous E450 chassis, the residual draws would deplete the chassis battery in two weeks to the point the coach wouldn't start. I had a Trik-L-Start but unless you are connected to power, the batteries discharged. Found the only way was to disconnect the ground to the battery and reconnect it when i wanted to use it. That insured there was minimal drop in the chassis batteries. Good luck,

[RaisingCajun]

Originally Posted by cinbol

Yes that WAS the issue. The chassis battery would loose voltage to the point where the engine would not turn over. The change in battery brands seems to have fixed the issue. We found some very small things like the aux radio button left in the wrong position, but didn't seem enough to be causing the dip...it seems the DIE HARD battery was just not worthy and we seem to be doing fine now. Thanks.

I am having the exact same issue right now. What brand of battery did you buy to replace your Die Hard?

[cinbol]

Originally Posted by RaisingCajun

I am having the exact same issue right now. What brand of battery did you buy to replace your Die Hard?

Our mechanic recommended the AC DELCO Professional and it seems to be working just fine. We have left the rig unused for a period of two weeks or more now between starts, and no issues with start up when we are ready to go again.

This battery just doesn't seem to "drain" as quickly as the die hard did and again I will repeat - the battery wasn't DYING it was just dipping to a charge level that was not sufficient to start our Ford engine.

Good luck!