Why do my batteries keep dying?

[lerossi707]

I have a 2002 roadtrek 190, it often sits for several weeks/months at a time, and each time I go back to start it it is completely dead. Last time I noticed the fan and ac we’re running even without the vehicle turned on. Two questions:
1. Why would the chassis ac/fan run with the key removed from ignition?
2. Is there a camper switch that decouples the chassis battery under the hood from the camper battery in the drawer? Does the coach battery run the ac and fan, or is that the chassis battery?
I’ve read a bit about the battery disconnect switch that it should be off if the vehicle is not moving, and read somewhere about an inverter switch too. Where is this located? Thank you!

[mkguitar]

Hi and Welcome to the Forums


i don't have your model and guess it is a dodge or chev



When parked at home I have a trickle charger on the chassis or "van" battery which comes on for an hour each night ( timer)

I have a chev, some of which have a persistent battery drain issue with the "speedometer head" ( GM's words) & add the security system


( I work on electronics, I spent a day testing circuits for a parasitic drain and traced from underhood fuse box to under driver seat fuse box to the speedo circuit)


I do have a disconnect on the NEGATIVE battery pole, I use this if parked camping for more than a few days

on the chev this results in the ECM loosing stored data and the van sometimes runs rough for a short period unto the computer "relearns" idle speed.


I use something like this for my side pole battery
https://www.amazon.com/Ampper-Batter...&tag=cb-osp-20


a battery which is fully discharged will often loose 50% of it's rated capacity- test yours it may be toast


the "house" battery will have a disconnect switch somewhere, this should be off when you are not using it - isolates the battery for all loads in the RV and also from the chassis battery. good idea to charge that battery once in a while when stored


if your ac fan is on, that indicates a wiring issue or the ignition switch.


on the GM the ignition switch is also dependent on the brake pedal depressed and the gear lever selecting park to turn off/remove the key.
I just went through an issue on my 2001 gmc pickup and found a broken spring which returns the gear select to "P" and allows ignition off and key withdrawn.
also a heavy key chain will wear and damage the lock tumblers on the ignition, possibly causing and unintended "on" or "off" condition



also make sure you door switches are working, on mine the side door switch contacts if dirty or broken can make the van think the side door is open and turn on the dome light. cleaning off oxidization is the fix





mike

[booster]

Originally Posted by lerossi707

I have a 2002 roadtrek 190, it often sits for several weeks/months at a time, and each time I go back to start it it is completely dead. Last time I noticed the fan and ac we’re running even without the vehicle turned on. Two questions:
1. Why would the chassis ac/fan run with the key removed from ignition?
2. Is there a camper switch that decouples the chassis battery under the hood from the camper battery in the drawer? Does the coach battery run the ac and fan, or is that the chassis battery?
I’ve read a bit about the battery disconnect switch that it should be off if the vehicle is not moving, and read somewhere about an inverter switch too. Where is this located? Thank you!

If it is the dash climate control blower fan you are talking about, it is very possible that the relay for the fan is stuck on. The often control only the coil or that relay with the ignition and running, and the relay inputs continue to have power. Check the fuse box covers or owners manual to see where that relay is and see if unplugging it stops the fan.


The isolator in the van should not allow the coach batteries to be killed by the dash blower fan, so it that is happening it is likely the isolator of some kind of short between the two sides.

[jeslaughter]

The isolator should protect the vehicle battery from discharge, however given the age of your vehicle, it may no longer be wired correctly. In many cases mechanics have bypassed isolators instead of replacing them. I've seen this more than once. Don't assume you still have as as delivered configuration.

The vehicle AC fan runs from the vehicle battery / alternator and has nothing to do with the coach battery. I would check the ignition switch. On many vehicles of this age the key can get so worn that you can remove the key the ignition in the run or accessory position.

There are lights in the compartments of most Roadtrek's which are connected to the vehicle battery. These can easily be left on draining the battery.

The under hood light can malfunction and stay on when the hood is closed.

The idle or ignition off current for a Chevy of this vintage is about .012 amps. With a good battery it can sit idle for 5 weeks or more, but not indefinitely. You will need to either disconnect the vehicle battery or connect it to a charger. Disconnecting the battery is a very reliable way of doing this since you are not depending on the charger working or being plugged in. If you check it regularly then that is not a problem.

You can check the "idle" or standing current, but it is a little involved in that you must allow the computer to "sleep" without interrupting the current. Measuring a small current by disconnecting the battery ground connection takes a little careful thought but it can be done. Don't try this unless you are sure of what you are doing. I use a special test cable which allows me to connect the battery ground cable via a jumper and once I am satisfied that the computer has gone to sleep I then connect my ammeter and remove the shunt. If some opens a door for example you might damage your meter.

Look for the obvious things first, left on lights, loose ignition switch. You may have a weak battery and you are expecting more than it can deliver after having set for 5 weeks.

Good luck,
John
2002 190V Chevy

Originally Posted by lerossi707

I have a 2002 roadtrek 190, it often sits for several weeks/months at a time, and each time I go back to start it it is completely dead. Last time I noticed the fan and ac we’re running even without the vehicle turned on. Two questions:
1. Why would the chassis ac/fan run with the key removed from ignition?
2. Is there a camper switch that decouples the chassis battery under the hood from the camper battery in the drawer? Does the coach battery run the ac and fan, or is that the chassis battery?
I’ve read a bit about the battery disconnect switch that it should be off if the vehicle is not moving, and read somewhere about an inverter switch too. Where is this located? Thank you!

[michaelingp]

Originally Posted by lerossi707

I have a 2002 roadtrek 190, it often sits for several weeks/months at a time, and each time I go back to start it it is completely dead.

Every vehicle puts some load on its battery when it's not running. This is called "parasitic load" and it's usually small enough that a vehicle can sit idle for a month or more and still start up. So, there are two possibilities: 1) your battery is not in good shape and thus can't handle the normal parasitic load, or 2) your parasitic load is abnormally high (or you're sitting idle too long).

So, first, have the battery tested. Second, have your mechanic check the parasitic load. If the battery is bad, replace it. If the parasitic load is higher than normal, you need to find out what is on that shouldn't be. If the load is normal and the battery is OK, then you need to use a trickle charger if the van is going to be idle for more than a couple of weeks.

I’ve read a bit about the battery disconnect switch that it should be off if the vehicle is not moving, and read somewhere about an inverter switch too. Where is this located? Thank you!

As others have mentioned, stuff connected to the coach battery should not drain the vehicle battery. But the battery disconnect should be off anyway to protect your coach battery. Your Roadtrek did not come with an inverter (a device that converts battery power to 120Volts AC). If you have one, you do want to make sure it's off whenever you are not using it, since they usually draw about 1 amp even with no load on the AC side.

As someone else mentioned, if you have light in the side cargo compartment (accessed from the outside, driver's side) make sure it is off, or better yet, remove the bulb.