All Electrical Dead, Coach and Chassis

[cvd]

2025 Europa 31 w Xplorer pkg, last driven about 10 days ago. Today, all DC systems are dead (coach and chassis). Only sign of life is the Victron; the gauge on wall and app both show 13.2 V, 100% SOC. Firefly won’t light up at all (app or physical screens). Pushing the Battery Disc button in the doorway doesn’t help.

Chassis 12v functions (e.g. ignition, headlights, levelers) also show no sign of life. Holding the dash battery icon button doesn’t allow ignition to function.

In battery bay, the 2 lithium coach batteries both show 13.2V. Chassis batteries show 2.9V (basically dead).

I connected shore power, which allowed the microwave to function and started charging the chassis batteries. After 45 min, the chassis batteries showed 12v, the ignition lights lit up and the leveler control panel lights. Those chassis battery driven systems seem ok, (other than the dead batteries, letting them charge now). The coach 12v battery systems still don’t function at all.

Background – possible causes: About 10 days ago the coach was driven, then parked. I installed Snapads, which involved running the levelers up/down 6 – 7 times. RV hasn’t been operated since. Can’t imagine this completely draining the chassis batteries.

I also recently installed a magnet in the door jam to “fool” the auto step retract/extend and allow the steps to remain in, even with the door open. All this does in emulate the door being closed, can’t imagine it causing a drain.

Questions:

• What would cause the chassis batteries to drain completely over 10 days?
• Why are my 12v coach systems dead? Batteries are good. Both disconnect switches in the battery bay indicate “On”. Plus, a voltage check on output side of those switches show current is getting through them.
• I’m wondering about the red Battery Disc switch in the doorway. I thought it was a toggle (on/off) switch, but it’s acting like a single pole momentary switch. I push it in, and it comes back when I release. Is my memory off base or is this switch bad?

Suggestions?

 

[malmz]

Q3: The red battery disc switch is a momentary switch, spring loaded. Push once and you should here the solenoid engage, push again the solenoid will disengage. The relay needs to have power to it to function though (I am not sure where from). Have somebody hold the dash jumpstart option momentary switch on the dash while you push the red momentary switch at the door to see if it clicks.

 

[Aussieguy]

battery disconnect should not be a momentary switch
you turn battery ON or OFF and it should stay as you switch it

I think... the momentary switch you talking about is a battery parallel... in case battery goes flat you can hold it to try and put enough charge into starting battery from the house
so you can attempt to start the motor.
I believe they make that switch momentary so you don't forget to disconnect the parallel.

chassis battery should last for more than 10days ... but you have to confirm nothing on the chassis side is left ON and draining the starter battery power.

For storage..
make a plan that enables you to charge the house and not the lithium (if in cold weather for lithium charging)
or fully charge the batteries as much as possible and disconnect them fully from any loads

disconnecting can be as easy as simply removing the main negative connection from the house and chassis banks

 

[png31]

As far as the chassis batteries, when ever a chassis battery suddenly discharges that quickly, the two most common causes are either a constant draw (any possibility you left something on, and do you normally shut off the chassis battery switch when placing in storage?), or failed battery. If one of your chassis batteries was on the edge of failure, repeated leveler cycling ( although I wasn’t aware those were powered by the chassis batteries) could have failed it, and it then depleted its companion battery. A full test of both chassis batteries is in order.

The mystery is why the seemingly functional coach batteries will not power the 12V system. You said you had power past the shut off switch. Have checked further down line?

 

[bclemens]

1 There is a chassis disconnect on the driver side floor right by the seat. If it is the push button on...those have been a bit finicky at times from Freigtliner

2. The RED disconnect at the Door, is ONLY a disconnect for the G12 (12V items) and it is a momentary switch. It powers the BD160 which is the battery disconnect. At times, there is programming in that switch that can get lost. If the batteries are saying 100% and the switch is not turning them on....press the red switch down and HOLD it down for like 10 seconds. That reprograms the BD160. It will either come on when you release, or you need to press again. I can't remember which.

 

[bclemens]

Some people found they could get it working by grounding the signal wire (porple) and load (Middle contact) with an insulated wire. This is what engineer said about it the last time it happened.

"Several things may be happening. If the disconnect disengages the BD160 but does not reengage it, the BD160 may have had its programming messed up. This can be fixed by grounding the SIG terminal of the BD160 for 10 seconds. Remove the ground from the SIG terminal and the BD160 should then operate normally by momentarily grounding the SIG terminal for ON and OFF states. If the BD160 does not operate at all from the switch, a wire may just have fallen off the switch terminals"

 

[malmz]

There are pictures of that disconnect to help find it at: Owner's Kit

Functionally the BD160 and BD225 are the same, the owners manual for a 2025 Europa comes up as this one on the Dynamax owners manual website.

 

[cvd]

Thanks Brian. I had just tried touching the Signal post to a ground momentarily (as the manual said). No luck. Holding the Signal to ground connection for 10 seconds (as your engineer said) did the trick. Coach DC power is now controlled properly via the doorway Battery Disc switch (a momentary switch).

Half the problem solved, I'll keep an eye on the chassis battery voltage as it sits over the next week or two. Must be some sort of draw.

 

[bclemens]

I do think the same thing can be accomplished by holding the button down for 10 seconds. that resets the memory;

 

[Aussieguy]

Must be some sort of draw.

to measure and find draw from battery
use a multimeter

NOTE... if your battery dies within a day... you got a BIG drain ... which may be a lot more than the small meters can handle
over 10amp will blow the small fuse inside most small multimeters

If you going to BUY a meter and expect to use it a lot....... to measure amps etc
spend a bit more money and get a meter with an amp CLAMP... hobby/budget meters are around $60-80
last time I looked..