Chassis battery

There is another possibility: relay, starting motor and solenoid that engages that motor. It’s not a big or expensive job to replace those with reconditioned parts. It happened to me when parking at our local hall. I left it overnight and replaced the starting motor in the morning still at the hall.

My experience with starting batteries is , if they deplete too long for a period of time their life is shortened.

Isolate the battery. Why dont you remove the cables, clean them and the battery terminals. Top off water and charge the battery fully while not connected to the rv.

After you charge it and remove the cables put a volt meter on the battery to check voltage, 12.6 Volts plus is fully charged. Leave the battery tor a few days to a week and check it again, see if its still fully charge at 12.6v. See if it holding its charge.
If not, you probably have a damaged cell and i would replace it.

If your rv does not have an emergency cut off switch then you need add one or remove the cables while you long term park it.
On the new battery or if the old one is acceptable , install an inexpensive cut off switch, like a knife switch onto the battery terminal. This is used to kill the power flow from the battery.
You will need to eliminate any parasitic drain that your truck is causing on your battery. Its being drained over time while sitting idle. Depending on the amount of the drain idle could be a week or more.

One post mentioned it and I will here again.. Load test is the only way to tell if the battery will take a charge and hold it. I am suprised I don't here this mentiond more on these types of discussions.

Dusty R wrote:
I figure 10 years on an engine battery.

Dusty

It really depends on how well you treat it -- 3 - 5 years is typical for a car or light truck battery that gets daily use. An RV chassis battery is usually used a lot less than a car battery so *can* last longer if you take care of it well, but a lot of people don't -- like it gets stored for months at a time out in the heat/cold without a charge, water isn't replenished or replenished with mineral laden tap water, it gets deeply discharged during camping when someone forgot to unplug the backup camera after parking, etc. So many cars come with maintenance free batteries these days that many people don't even know that they have to check the battery water level.

In my case, the water was so low in my new (4 year old used) RV battery that the water was well below the plates in a couple of the cells -- I found this out when I was doing the delivery inspection and noticed that the engine turned over slowly and got them to throw in $100 towards a new battery (they said they'd replace it for free, but I didn't want them to put in a cheap battery). I suspect they noticed the bad battery and relied on the boost switch, but thought I wouldn't.

I figure 10 years on an engine battery.

Dusty

pappaone wrote:
Having problems starting 2017 Minnie Winne mh. Was able to get the engine started using the house batteries switch and chassis battery reads 14.5 while running. Let it run for awhile then shut the engine off but wont restart using just chassis battery. Is it possible the battery is not strong enough ?

The voltage while running doesn't really tell you the state of the battery, it just tells you that the charging system is working (but not how well it's working). 14.5V is around the top end of the range it should be so it seems like the battery should be getting a charge -- try the test @whemme recommended above and check the voltage with the headlights on for a simple load test.

Starting batteries don't handle deep discharge well, so if it's been run down frequently, it may just be at the end of its life. Typical starter battery life is around 3 - 5 years, so it may have just reached the end of its natural lifetime.

Sounds like a dead chassis battery to me. Some of them die young.

Before you ditch your battery, clean the posts, cable ends and top of the battery thoroughly with water and baking soda. Even if a batter looks clean a light, invisible film on top can create a draw from one post to the next slowly draining a battery. You might also check your alternator output to be sure it is charging the battery properly. Some chargers have an alternator check on them or maybe a battery store will check it (If you trust them to tell the truth vs selling you something). And of course if it is a wet cell, check the water level inside.

pappaone wrote:
Having problems starting 2017 Minnie Winne mh. Was able to get the engine started using the house batteries switch and chassis battery reads 14.5 while running. Let it run for awhile ...

What is "awhile". If you had to use the house battery to start it, it would take at least 30 minutes of highway driving to get a reasonable amount of charge back into the chassis/starting battery.

My bet is that it is time for a new battery.

What does your chassis battery voltage indicate with engine off but with headlight switch turned ON? If below 10V your chassis battery is dead or badly discharged.