Chassis & House batteries dead

[Vicap]

This morning the chassis battery was dead on my 2021 Tellaro 20kt. There wasn't enough juice in the house battery due to several days of rain/overcast skies not allowing solar panels to charge them. I plugged the RV to shore power & after a few minutes, was able to start the RV off the house batteries. A yellow check engine light is now on.

So my question is: would the house batteries drawdown drain the chassis battery?

Does a drained chassis battery automatically cause a check engine light to illuminate?

[code2e]

Originally Posted by Vicap

This morning the chassis battery was dead on my 2021 Tellaro 20kt. There wasn't enough juice in the house battery due to several days of rain/overcast skies not allowing solar panels to charge them. I plugged the RV to shore power & after a few minutes, was able to start the RV off the house batteries. A yellow check engine light is now on.

So my question is: would the house batteries drawdown drain the chassis battery?

Does a drained chassis battery automatically cause a check engine light to illuminate?

Ideally, the house batteries are isolated from the chassis battery to prevent just this occurrence. There should be a battery control center or at least a solenoid that keeps batteries isolated.

Is it possible something that draws from the chassis battery was in use or left on? Common items might be the dash radio or lights such as glove box or map.

In my career, when jump starting a dead battery, I would not allow the driver to get inside. I would hookup jumpers and we would both look in a window. Many, if not most times, there was a light that came on or a key left on. You see, lights always go out on their own once the battery goes down.

The check engine light is likely related to low power and / or the recharge. It would be a good idea to stop by a major auto parts store, like Autozone. They will scan the code that turned on the light and tell you what it is, at no charge.

[robertj1979]

Originally Posted by Vicap

This morning the chassis battery was dead on my 2021 Tellaro 20kt. There wasn't enough juice in the house battery due to several days of rain/overcast skies not allowing solar panels to charge them. I plugged the RV to shore power & after a few minutes, was able to start the RV off the house batteries. A yellow check engine light is now on.

So my question is: would the house batteries drawdown drain the chassis battery?

Does a drained chassis battery automatically cause a check engine light to illuminate?

If your check engine light is on I would suspect you could have a problem with the alternator that is supposed to charge the chassis battery. Even if the house batteries are drained, should not kill your chassis battery. If you can use a voltmeter, check the chassis battery while the engine is running and also while not running to see if there are different voltages (engine running voltage should be higher). I would also check your serpentine belt to make sure it is place. There have been some problems reported with these on some models due to Thor incorrectly routing a new belt with the under hood alternator models.
If not familiar with how to use a voltmeter, agree with the idea to go to Autozone or similar store and they will check it for you. Please report back what you find as could help someone else.