I have a 2011 Jayco Greyhawk 31DS. The chassis battery is almost toast. Other then resetting the stereo presets will anything else go south when I disconnect the old battery and install the new??? I wouldn't think so, but thought I'd check..

Possibly the engine and trans CPU. I just found out 15 mins ago that when you pull the chassis the battery the whatever engine parameters are used for smog checks are erased and the vehicle needs to be driven to accumulate enough data for an accurate measurement again.

So it's kinda like clearing error codes. It has to be driven a while to let all the sensors fire.. That's fine. I'm gonna replace the battery tomorrow and take it camping for the weekend. Should be about 200 miles there and back. That ought to set it all straight.....Thanks

If you have the Ford Chassis Owner Manual, check there for battery replacement guidance. I think you're safe simply disconnecting, changing battery, reconnecting. Used to be the Radio had a Security Code and if you couldn't re-enter it, the radio would no longer work, and anti-theft measure. I don't think that's common anymore.There's a "memory saver" which is essentially a little 9V battery that you clip to the battery cables before disconnecting. It's supposed to save things like Clock, Radio Stations, and Driving Patterns. But some owner manuals contain specific wording to NOT use one.

2011.... any warranty? Seems like an early death.How do you keep the battery charged between trips or while camped?I think you can use a 9 to 12v battery to keep the memory from deleting.

I run the gen and the engine every two weeks..Worked for over two years

Battery replacement | Good Sam Community

ron_dittmer
Explorer II
Jan 17, 2014
As others mentioned, you can keep your computer and radio memory during a chassis battery swap through a 9 volt adaptor like this one.

I have recently heard that if your cell phone is fully charged, turn it on and plug it into a 12v outlet as if to charge it and it will accomplish the same thing. But I have not personally confirmed this.

Whether using a 9v battery or a cell phone, make sure the 12v outlet you use is powered up even when the ignition is off.

I don't worry about the computer, radio stations or clock. I disconnect both the chassis battery and the coach batteries off-season to prevent significant discharge.
RambleOnNW
Explorer II
Jan 17, 2014
j-d wrote:
If you use a chassis battery disconnect, you'll force the PCM to re-learn your driving every time you use the RV. Not to say that's prohibitive, just that about the time it gets to know you it'll forget you.
I shouldn't claim this, but I just don't have battery problems. I can go two months (Florida weather) and the house battery (which I do disconnect with the shutoff Jayco provided) will start the genset. The chassis battery (11 years old!) will start the road engine. Can't say I know where the power comes from the radio... It's aftermarket, and will always play when the engine's running, even if house battery is OFF. Engine off, it'll play if the house battery is ON. In any event, the batteries hold up.

The electric steps drain the chassis battery in our Jayco down to the 50% level in about 1 month. So I disconnect the battery each time we are not using it for a while. Have not noticed any driveability issues each time the the ECM has to retrain after reconnection of the battery and driving for the next trip.
Cruisineasy
Explorer
Jan 17, 2014
Nice. I may have just had a bad battery in the thing. The "eye" on the top of the battery was green for several months. Red this past year..
j-d
Explorer II
Jan 15, 2014
If you use a chassis battery disconnect, you'll force the PCM to re-learn your driving every time you use the RV. Not to say that's prohibitive, just that about the time it gets to know you it'll forget you.
I shouldn't claim this, but I just don't have battery problems. I can go two months (Florida weather) and the house battery (which I do disconnect with the shutoff Jayco provided) will start the genset. The chassis battery (11 years old!) will start the road engine. Can't say I know where the power comes from the radio... It's aftermarket, and will always play when the engine's running, even if house battery is OFF. Engine off, it'll play if the house battery is ON. In any event, the batteries hold up.
Cruisineasy
Explorer
Jan 14, 2014
Success!!! Just changed it out with no problem..
Since I don't set up the stereo with presets, would it mess things up if I rigged a disconnect for the chassis battery???
pianotuna
Nomad III
Jan 11, 2014
Hi,

You might find that if you added the solar and the trik-l-start that the chassis battery may come back to useful life.
time2roll
Nomad
Jan 11, 2014
Cruisineasy wrote:
I run the gen and the engine every two weeks..
Worked for over two years
This is where I think 100w of solar on the house battery and a Trik-L-Start combiner to keep the chassis battery charged would be less wear on the engines and add life to all batteries.

(assumes the roof gets at least occasional sun)
tatest
Explorer II
Jan 11, 2014
Relaced my 2003 vintage OEM battery in 2008. Engine - transmission computer will rest to defaults, had to relearn my driving style, shifts were back to "normal" after first 100 mile trip. Not sure what happens with keyless entry, if you have that.

Did not have radio issues, have aftermarket radio which I disconnect anyway, don't use any presets. Radio house-chassis switch to house, the house batteries disconnected. Some radios on battery in storage will pull it down pretty fast, and in a way that damages lead acid batteries permanently, way below a normal voltage for "complete" discharge. Engine control unit can also do that, takes longer.
Cruisineasy
Explorer
Jan 11, 2014
I run the gen and the engine every two weeks..
Worked for over two years
time2roll
Nomad
Jan 10, 2014
2011.... any warranty? Seems like an early death.
How do you keep the battery charged between trips or while camped?

I think you can use a 9 to 12v battery to keep the memory from deleting.