12v battery problems 1990 Winnebago Micro Warrior (Toyota chassis)

[montgoli]

We have 1990 mini Winnie micro warrior and having problems with 12 volt battery. The battery is saying it’s charged but since we plugged into the 120 V none of the lights work..only the big items like AC and fridge work…we just had a new converter installed. A relay in the battery compartment is making a clicking sound. We checked fuses and all look good but am wondering if there’s a fuse we’re not checking. Also just had hot water heater installed but the switch for that runs off the 12V so that’s not working either. We’re on our maiden voyage with her!

[creativepart]

I looked up your RV and since most of us have never heard of a Micro Warrior on a Toyota truck chassis I grabbed a screen shot. Here's what they look like:

[Morich]

We may need some more info on which RV you have as none seem to match exactly.
Can you spot which from this list? If that is not handy or top of the head, there should be a label on the driver's left side with that info.
With that info we can go to the correct drawings with a bit more confidence!
Click this snip to get better view!


But as a general good place to start, perhaps try starting the RV engine and see if that changes any of the issues like the lights working. The thought is that when the engine is running both start and coach batteries are connected together with the alternator. If having the start battery tied in makes things work, then we might need to look closer at the coach battery charge and if any connections might be dirty or corroded!

[montgoli]

That’s our baby…I tried to attach a pic but wasn’t able to because it wants a URL too attach photo?? Anyways any info about the battery issues would be greatly appreciated! Thanks!

[montgoli]

Model number WT319RB it doesn’t appear to be faulty connection we already disconnected and reconnected and it’s not the Toyota truck battery it’s the battery that powers the lights in the back and all other 12V things

[Morich]

Got the right drawing pulled up.

When you try to crank the generator, does it crank as if it is getting power before starting the RV engine ?
And if not, what does it do when the engine is running?

Can you see this relay you hear clicking and when is it clicking? Is it clicking as you turn the key on and off?
That would likely be the mode solenoid and normal for it to click as the ignition is turned on/off. If you can see that solenoid it should be a silver "can" with battery cables to each side and one or more small wires in between the larges cables on each side. That is what we expect to connect the two battery groups together.
The reason for checking power to the generator and then rechecking after the engine is running is that will prove out the condition of the coach battery and wiring.
If the generator will crank on the coach battery, we can say it is good, but if not and then will crank when the engine is running, it will be because it is getting power to crank from the chassis/ start battery.

[montgoli]

Ok, we will try cranking the generator first to see if it starts…then turn engine on to see what happens. The clicking sound was not happening when we turned the key on and off because we haven’t tried that yet…it started happening right when we plugged into the 30. We disconnected the (marine) battery and reconnected it and there’s no more clicking sound. Well let you know what happens. Oh and we also tried disconnecting the big 30 amp and just plugged into regular outlet and still nothing

[montgoli]

The generator starts fine and tested auxiliary battery at 95%. When we started the engine again, the clicking began again. Still no 12 V, lights, etc.

[Morich]

Do you have a way to test if 12Volts DC is on a point? A meter would be good but a test light or something that uses 12Volts might work?
There is a load center looks like at the end of one dinette seat. When you open it the left side is 110AC and you need to be careful what you touch on that side!!
The right side is 12VDc and much safer to work on as long as you are careful not to short two points together!

What we see so far says power is getting straight from coach battery to generator starter as green line shows here.
But the rest of the 12Volt coach things work off the load center.
Click these snips to see better! Or go direct here to get full 12volt DC drawing. https://www.winnebago.com/Files/File...990/095714.pdf

This is what to expect when opening the load center. Hot 110AC if plugged in will be on left.


The 12VDC is on right with fuses. It should be 12volts in on lug at top right with good ground on the lug next lower!


I'm guessing that you will not find 12volts and ground on these two points?
I might guess the breaker I marked in Red is the problem. But I can't see where the solenoid nor these breakers are located. Got any thoughts on that? Maybe in with the coach battery or close by?

[montgoli]

This is fantastic! We don’t have a tester right now but we do at home and will run the tests you suggested either tomorrow or Saturday and let you know what happens. The time you have invested into helping us out is greatly appreciated!

[montgoli]

Hi.

Here is a pic of the aux battery compartment. Battery shows over 12 v power, but no voltage at the control center. When I hook the black wire from the relay to the positive terminal of aux battery, the middle relay makes repeated boing sounds.

No 12v on first nor third relay but 11v shows on middle relay (I think the one that is making boing noises), but no voltage on the other relays.

There is a big spark when I attach the black line from the first relay to the
+ battery, which seems unusual.

None of the 12v system works inside, whether on battery or shoreline.

Thanks!

[Icbigfoot]

Those could be circuit brakes, not relays, but there's no reset buttons on them.

[creativepart]

Originally Posted by Icbigfoot

Those could be circuit brakes, not relays

Yeah, those are not relays. I'm not sure the real name for those but it's more like a fuseable link. At least in my layman terminology that's what I call them.

[creativepart]

Originally Posted by montgoli

Battery shows over 12 v power,

Be aware that a fully charged Lead Acid battery (flooded or AGM) has a voltage of 12.7 to 12.8 volts ONLY.

When you see 13v to 14v you are not seeing battery voltage. You are seeing charging voltage. The battery could be totally dead but if it's being charged by shore power, generator, alternator or even solar it will show you the voltage of the charge current.

And, if you turn off the charger it will hold on to that reading for a short while after but it's just a surface charge leftover from the charging.

So, when you tell us the battery is over 12v to prove that your batteries are good we immediately are suspect of that reading and the true condition of your battery.

Unplug, turn off all charging from the generator, the engine alternator, the solar charge controller, etc. Let the battery sit for 6 hours then test the voltage. Now you're seeing your batteries voltage. OR if you have flooded lead acid batteries you can use a hydrometer to test specific gravity to learn turn battery condition at any time.

PS. This doesn't apply to Lithium Batteries. Most of them are between 13.5 and 14.3 volts.

[Morich]

I think those will be breakers rather than relays. Some are called different names indifferent places. Reset able, self resetting are a couple names. With a button to push, I call them resettable while self reset are meant to reset when they cool.

I think you are looking at some wire connectors that have been replaced since new, so other changes may be found , too.
But I'm guessing what you have found is what is shown in post 9 and the first picture! See how there is a black number 10 coming from left and then another going out to the right. and then another?

I think that will be 12volt battery coming in at one end of a breaker and going like in a daisy chain out to the next breaker and to the next!
I would expect to find all those three black wires to have 12+ volts on them, Then if you look at the other end of the small breaker , it should also have the same voltage if the breaker is good!
Unless one of the breakers is tripped, all the screws should have 12Volts!
Click this to see better.


In on the red path, through a breaker (if good!) and then split to go different items like blue path!
If most all the RV 12volt is dead, the panel in my picture above may not be getting 12Volts at the right side. If no voltage on the lugs where it comes into the load center, that cuts off all those fuses and lots of things go dead! One of these may not be passing the power as it should.
While looking at this point check that there is voltage on the actual wire or connector if you can.
Corrosion is a big thing on RV that set for a while and there may be voltage on the screw of the breaker but not getting to the wire, so be alert for tricks !

[Icbigfoot]

Hi.

I tested the battery (12.5 v) and each of the connections to each of the circuit breakers mounted on the side of the battery compartment. All showed 12.5V except for the outgoing terminal on the middle breaker, which showed no voltage.

Therefore, ordered new breaker and hopefully that will fix the no 12 V problem inside the Winnie.

But I cannot understand why there would be no 12V working when hooked up to shore.....

[Morich]

Understand that the breakers are simple safety items to protect us from melting the wires down if we get a terrific short somewhere.
That leaves us some slack for short time testing of what a good breaker would do for us.
If the breaker is not passing power through and you have lots of things not working, one quick, easy test is to put a wire across the breaker for a short time while we find what it makes jump up and work!

NOTE!
This is NOT something to leave on there for long term use! Just put a temporary jumper across from one screw connection to the other long enough to go check if lights, etc. now work!
One way to increase the safety of this even more is to look at the size of wires going in and out of the breaker and use a smaller jumper wire.
Worst case is that there IS and actual short in the wiring beyond the breaker and if we wire around the breaker, the existing wire could get too hot and cause problems.
But if we use a smaller jumper wire than the existing wire, that smaller wire will overheat and we should see that before harming the bigger!
But if we just leave the jumper long enough to flip a few switches inside, we are not likely to overheat anything!

OUCH! I just noticed we have a different person posting? That really makes it hard to keep the info straight as they are often different problems that need different solutions!

[Icbigfoot]

The problem seems to be that the circuit breaker keeps tripping, although it self-resets and the current runs through at 12.5V. As soon as I connect the lead to the battery, it trips. I assume this breaker needs replacing. But is this an indication of a short somewhere else?

[Icbigfoot]

Haha, yes, husband is Icbigfoot, Wife is Montgoli.

Thanks, I will try to jump the breaker.

[Icbigfoot]

Hi Morich.

When I jumped the 2nd breaker, the line from the battery to the breakers got VERY hot instantly.

Still nothing at the 12V side of load carrier inside.