No 12 v in motorhome

The friendliest place on the web for anyone with an RV or an interest in RVing!
If you have answers, please help by responding to the unanswered posts.
I can’t seem to find a “salesman switch” anywhere.
That AUX BATT switch is your battery disconnect switch. Your battery disconnect system may not be your problem but if the rocker switch pressed to OFF your 12V system is disconnected from the battery. When coach on 120V power your converter/charger converts 120V to 12V for your 12V systems.

Rock that AUX BATT switch to see if 12V lights come on or hear a clunk sound.

Your converter/charger and 12V fuses appears to be working since your 12V system works with 120V power. There may be fuse types after fuse panel and batteries so check wiring diagram if problem persist.
 
The power step on the entrance to my motorhome works, but nothing else.
The step is powered by the chassis battery and not dependent on the coach for power
With shore power, everything works. No Shore power, all is dead
This indicates that your 120V/12V converter is working but either your batteries are disconnected or they are discharged. You may have a battery isolator switch somewhere but you really need a meter to find the problem. Have you looked at the coach batteries?
 
The step is powered by the chassis battery and not dependent on the coach for power

This indicates that your 120V/12V converter is working but either your batteries are disconnected or they are discharged. You may have a battery isolator switch somewhere but you really need a meter to find the problem. Have you looked at the coach batteries?
Yes, the coach batteries are very good and fully charged
 
FYI....Many 2002 ish charging designs did not include chassis battery charging from the converter/charger. The converter charger was dedicated to the house batteries.

A simple voltage check at the chassis batteries while plugged in with chassis engine off, will provide you with what charging design you have. This assumes the converter charging function is functioning properly.

To check the converter charging function, check the voltage at the house batteries while plugged in with chassis engine off.

The above 2 voltage checks will be very helpful.
 
Last edited:
Check the fuses on your converter.
Since he has 12V when connected to shore power, his converter must be working.
Yes, the coach batteries are very good and fully charged
I am wondering how you know this if you do not have your meter? If the batteries are charged and you still do not get power from them, either you have a battery isolator that is open or there is some problem in the connection between the battery and the 12V distribution panel where the fuses are located.
 
I am thinking disconnect is ... In the "STORE" (off) position. As I said on my coach the disconnect was a remote operated solenoid. Well the Use/Store switched worked great for "Store" but dirty contacts so it would not "use" I fixed it.

If I knew more about HIS electrical system I could trouble shoot but alas. He'd have to describe and I'm in the Flint, MI area. Would be willing to visit campgrounds in this area.
 
Since he has 12V when connected to shore power, his converter must be working.

I am wondering how you know this if you do not have your meter? If the batteries are charged and you still do not get power from them, either you have a battery isolator that is open or there is some problem in the connection between the battery and the 12V distribution panel where the fuses are located.
When I am plugged into shore power everything works. No shore power, nothing works, and the coach batteries are 1 month old and fully charged
 
Hint, click on your screen name in the upper right, select signature and create a signature that contains the information about your RV including the EXACT model, ie 2002 Itasca Spirit 24F (Or 24V if that is what it is). Its actually a 324F or 324V but the 300 series is the Spirit, just like I had a Winnebago View 523H, but 23H was enough to get the point across, the 500 series is the View.

You can just download the bottom most link rather than the 12 individual links, however, the bottom link includes ALL year 2002 300 series Spirits and 400 series Minnies, and all floor plan variants, so you may not want that much info. In that is the case, download the 12 individual links to get all of the diagrams for your model only.

You didn't say whether you have a 24F or a 24V model. Here are ALL of the wiring diagrams for both models.
While I'm at it, here are the plumbing drawings...............
Pick your model, download ALL of the drawings, a dozen or so for the wiring diagrams, plus the plumbing, and save them on a thumb drive used for NO OTHER PURPOSE but these drawings and PDF's of manuals for appliances such as the water heater, furnace, etc. You never know when this stuff might just disappear off the internet. This is the value Winnebago adds to their product that, if you know what you are buying, makes it worth a little more.

Keep the thumb drive in the black Winnebago manuals pouch, it will always be there for your and future owners. Keep a copy on your desktop or laptop also.

Also, download this Winnebago RV Parts and Accessories Catalog, as it can be immensely helpful in identifying parts by WBO part numbers.

Also, download the parts catalog appropriate to your coach model..........

CharlesScreenshot 2024-09-12 213230.png
 
Last edited:
Open the storage compartment just aft of the step well. In it is a circuit breaker panel, of 12v breakers and the battery disconnect relay and the boost relay. If you cycle the salesmans switch to the left of the entrance, the battery disconnect relay should cycle. If it does not, there are two fuses in the relay that you can check. If it is cycling, then also check the circuit breakers to make sure they are all firmly pushed in.

Charles
 
When I am plugged into shore power everything works. No shore power, nothing works, and the coach batteries are 1 month old and fully charged
You likely understand the electrical systems powering your Class C but sometimes review helps.

Both Class A and Class C motorhomes have a 120V and a 12V power systems:

120V system power comes from external 120V Panel Outlet (20, 30, 50 amp sockets/pedestal) or generator. 120V powers the house style sockets. Disconnect from 120V and sockets have no power.​

12V power system gets it power from the house batteries or the converter/charger when on 120V. The 12V system provides power to the ceiling lights, the appliances circuit boards, ex. refrigerator, thermostat etc..​

The converter/charger convert 120V to 12V. When you are on shore power it is the converter supplying 12V power and not the batteries. The converter also is a charger to charge the 12V house batteries.​
The converter is why, when you are plugged into shore power/generator, both your 12V and 120V systems work. When you disconnect 120V you are relying on your batteries to provide 12V power.​
The AUX BATT or Battery Disconnect Switch purpose is to disconnect the 12V house batteries when you store the Class C. If the Battery Disconnect Switch is flipped to Off (STORE) the 12V battery will not provide power to the coach.​
Your lack of battery supplied 12v power is what would happen if the AUX BATT in Off position &/or problem with relay.

bzerull You never told us if you evaluated the AUX BATT rocker switch nor the relay. This really is the first troubleshooting step. As stated you should hear the relay make a clunk sound. It appears your AUX BATT does not have a light so I think the relay will have 1 5amp? fuse.

CharlesinGA has given you some good advice and we want you to solve the 12V power problem.

Jennifer
 
Last edited:
Thank you Jennifer. I will be back in town this weekend so i can check..yes, i do understand the electrical, but i can’t locate the aux battery rocker. I will review the electrical diagra and start with finding this switch. Which i should have somewhere, right?
I do know where the rocker switch is that supplies additional 12v power to the truck cab if needed. Your help is much appreciated.
 
You won't have to hunt for it in a cabinet or behind an access panel, check in "plain sight". Per the example diagram above it's in the doorway:

1726231876911.png

The documentation for your specific RV will have a similar location diagram. I haven't seen a huge number of RV's but every one I've encountered has the disconnect located somewhere near an ingress/egress point whether it's the house or cab/chassis door, in plain sight. The relay itself is likely co-located with the bank of DC breakers that are supplied by the relay, which is also likely located somewhere near the house batteries (adjacent compartment).

Mark B.
Albuquerque, NM
 
Yes, i have found this switch, left side of entry. I also have an outside storage, passenger side rear that has an outside shower. In this cabinet is a rocker switch with no markings or lights. Can’t figure out what this switch is for and have tried everything i can think of.
 
You won't have to hunt for it in a cabinet or behind an access panel, check in "plain sight". Per the example diagram above it's in the doorway:

View attachment 175226

The documentation for your specific RV will have a similar location diagram. I haven't seen a huge number of RV's but every one I've encountered has the disconnect located somewhere near an ingress/egress point whether it's the house or cab/chassis door, in plain sight. The relay itself is likely co-located with the bank of DC breakers that are supplied by the relay, which is also likely located somewhere near the house batteries (adjacent compartment).

Mark B.
Albuquerque, NM
Thank you Mark!
 
bzelrull,
That stairwell AUX BATT switch is the what Winnebago calls their battery disconnect switch. That is the one controlling the batteries thus the one related to 12V power loss and the switch we want you to troubleshoot.

If you tell us the year and
the EXACT model, ie 2002 Itasca Spirit 24F (Or 24V if that is what it is).
I am sure CharlesinGA would be willing to pull up Winnebago documentation to identify the passenger side outside shower storage cabinet rocker switch.

Jennifer
 
Yes, i have found this switch, left side of entry. I also have an outside storage, passenger side rear that has an outside shower. In this cabinet is a rocker switch with no markings or lights. Can’t figure out what this switch is for and have tried everything i can think of.

The second switch mentioned, is either a water pump switch or a light switch. More likely a water pump switch.
 
Last edited:
Yes, i have found this switch, left side of entry. I also have an outside storage, passenger side rear that has an outside shower. In this cabinet is a rocker switch with no markings or lights. Can’t figure out what this switch is for and have tried everything i can think of.
The second switch mentioned, is either a water pump switch or a light switch. More likely a water pump switch.
Water Pump.
Screenshot 2024-09-13 155016.png
 

Latest posts

Forum statistics

Threads
133,347
Posts
1,408,915
Members
138,905
Latest member
forever rver
Back
Top Bottom