Easy question for a not newbie like myself

[AmandaandMarky]

Hi all!

I’m having some battery/ electrical issues with my 2000 Ford ecoline e350 mini... it’s a diesel also. When I got it it started and ran without issue, the person before me was making it into a party bus and had subs and big speakers in the back of the bus. Once we removed those things went array. Can’t start the bus without a jump now. We also left the roof hatch open and thought the alarm may have killed the battery. We tried replacing the main battery and charging it all the way too...
My biggest questions I need answers to to know where to go at this point
- How many batteries are supposed to be required for this mode to run? I know we had one under the hood and then a second in the back which we thought was just for the music system, and a third by the wheel well, possibly for the lift it used to have or maybe one of those other two are required for starting? Please advise! I’m new and lost.

- secondly, it is getting to a point where I am not capable of doing this on my own, how do I find a person who can help with bus issues? Can any mechanic help with the battery stuff? Specialized?

Thanks
Amanda

[CHEESE_WAGON]

Diesels can start with one battery, but most have two for good measure. Most RVs and buses with handicap lifts have two in the main battery box, with an isolator to prevent the 'house' (auxiliary interior power battery) from draining the main batteries (for starting the engine). One possibility is the isolator is bad. It is an electrical check valve of sorts to keep the two from discharging each other, while allowing one alternator to charge both.

First, have all your batteries load tested. A battery with one or more weak cells will hold a charge when warm, but discharge in a hurry when it gets cold, so this is common in cold weather. A load test when the battery is cool or cold will tell the tale.

If they pass a load test, then something is causing a draw in the vehicle somewhere. At that point, I would recommend a qualified shop. If you are in or near New York State, I would recommend South Main Auto -- they have a guy named Eric that is excellent with electrical, has many YouTube videos demonstrating his ability.

[AmandaandMarky]

I am in New York State! Up a way by Syracuse but that is a bunch of helpful information. Thanks a lot

[CHEESE_WAGON]

To clarify, you may have two chassis batteries for starting the engine, and a third auxiliary battery elsewhere for house/handicap lift power.

[AmandaandMarky]

That could be, it’s confusing because the previous person had started converting into a party bus, nice start interior at least with the seats out and wood floors down and an inverter , but all the music amps and whatnot in the back we wanted Out and didn’t realize the battery back there may have served more purpose than just subs and amps. As far as I can see there is one under the hood, one really decrepit looking one under the whee well area, and the one in the back where the amps were all hooked in. Replaced and charged the one under the hood and bought a second battery but not sure where to put it

[AmandaandMarky]

Can any mechanic do this work? Do I need a diesel mechanic or bus garage?

[CHEESE_WAGON]

I don't believe this to be diesel specific, it is clearly an electrical issue. However, not every mechanic is all that great with electrical, either.

[Mountain Gnome]

My diesel Cummins 5.9L would not start without 2 batteries when it is cold. Maybe the decrepid looking one needs replacing also.


Disconnect the cables from the decrepid looking one. Fully charge the good new one under the hood. Then try to start. If it starts, the decrepid looking one is bad, and killing the good one. If it does not start, you still may need two good batteries in cold weather.



You can test to see if they are connected (they likely are) with a test light (or volt-meter). With the decrepid looking one disconnected, and the good one connected under the hood, use the test light to see if there is power at the cables for the decrepid one. If there is, they are connected, and the bus is wired to use two starter batteries.


Wish I could help more, but glad I'm not in New England!

[Mountain Gnome]

I forgot the rest! I'm bad at remote diag. ADHD or something...


When you turn the key to "start", does the motor spin and try to start? Or does nothing happen?



If is does not spin with the decrepid battery disconnected, and the battery under the hood is fully charged, then you likely have another issue besides batteries. Check to make sure all your emergency doors and the roof hatch are fully closed and locked. They may prevent the bus from starting.


If it does not spin but you hear a "clicking" sound when you turn the key to start it could be the starter, or a weak battery. Make sure you turn the key to "on" and wait for any clicking sounds you hear to end before you turn the key to "start" for this test. If this is the case, have your battery tested before replacing the starter.



If it does spin but does not start, then try replacing the second battery with a new one (technically you should replace both the one under the hood and the decrepid one at the same time, if they are connected, but if in a pinch, you can replace just one)



Gotta run now, but I'll check back, if no one else here takes over. Many good diag people here.