Basic battery question

Dan33

Senior Member
Joined
Jan 16, 2021
Posts
103
Location
St Louis
Just bought a 2009 2720 and it only has one barely working group 31 deep cycle battery and an empty spot where battery #2 goes .

Problem-. Nothing except for electric tongue jack works on battery power, no lights or fans. Electric 30amp works fine.

Next? Not sure what these wires are for but looks like I need a 2nd battery and/or need to redo all connections to get lights and fans to work on battery?

Any YouTube video that would guide a newbie on what to do next?


Thanks
 

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Manual

Thanks . Will take a look and see if the schematic will help me. Here are a few more pics . First RV
 

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Referring to the first pic in your original post. At the bottom of the pic, I see two wires coming from the battery post - a heavy black one and a red one. The heavy black one almost certainly runs to the second battery box, where it would be connected to the positive post of a second battery if one were installed. At this point it should be connected to nothing, and insulated from unintended contact with anything else.

The red one goes to a black plastic fuse holder. It is barely visible in the photo, outside the box and hidden under the green wire. Although it is a little hard to see in the photo, the other end of this fuse holder probably has a small black wire coming out of it. This wire carries power into the TM. If you open up the fuse holder (push and turn), you may find that it contains a 30-amp glass tubular fuse, that is either blown, corroded, or entirely missing. As a short-term fix, you can replace this fuse - any hardware store - and it will give you power back into your TM. Long term, you should replace the entire fuse holder with an automotive blade-style fuse holder. See

https://www.trailmanorowners.com/forum/album.php?albumid=8&pictureid=760

I can't spot where the power to the jack peels off, but it is somewhere in the rat's nest. But since the jack works, the fuse I mentioned may be good, and the problem lies farther down in the rat's nest.

If we need to pursue this further, you will have to pull the wires out of the boxes so we can see where they go, and what is connected to what. If you find another fuse holder in there, be sure to let us know.

This should restore power to your TM. If it does, we can explore the rat's nest of wires in the empty box. The connections are simple, and aside from the long messy wires, easy to understand and easy to connect. In the meantime, make sure that none of the bare wire ends in that empty box are contacting any other wires.

I doubt that the schematic will be of much help, but it can't hurt.

Bill
 
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Thanks, headed to the store to buy a a 30-amp glass tubular fuse which runs along wire I marked in purple and into the TM. I removed battery and exposed all, then circled wires by color to show where they run (green one in precious pics was a bungee).

I’m also replacing a group 31 deep cycle battery too as PO had no distilled water and noticed it was swollen when I was charging last night. No idea what the frayed brown wires are for but they are exposed so will tape those up (they run under TM). There is a 2nd fuse, a flat 20amp fuse going to the jack, only other one besides the tubular one. Really appreciate the help, and will keep researching posts as much as possible before asking questions.
 

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OK, you have two fuses. In your next-to-last pic, you have a purple circle around a black fuseholder labeled Atwood. The holder is open, and has a glass fuse showing. This is not the standard TM-installed holder, so it might serve the electric jack. Right next to it, there is an automotive ATC blade fuse holder (red wires) that Shane and I have mentioned. This isn't standard for TM, either, but is a retrofit commonly advised on this forum. My guess is that one of these holders has a good fuse, and one has a blown fuse. What are you finding?

Bill
 
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A slightly complex reply (WRT rewiring at the batteries)

Before I begin, let me advise of an insulation color change for "12v" electric wires between your 2009 TM (older USA standard colors) and your somewhat newer electric tongue jack (newer international standard colors):

In TM "12 Volt DC" wiring, the +12V wires are BLACK, the negative return wires are generally WHITE. In newer equipment, and especially in devices from China, the +12V wires are RED and the negative return wires are BLACK.

In all cases, +12V wires should be fused, and grounding wires should never be fused.
- - -
Your Electric tongue jack BLACK wire is bolted directly to the the "-" post of the battery. That post also connects a slightly larger WHITE wire (AWG-8) marked "Neg". The other end of that wire is bolted into the TM frame. Even though the conflicting colors look weird, this is correct. If the bolt connection into the frame is good and tight, then the grounding side of "12v" to the TM lights and other loads is good.
- - -
Your electric tongue jack RED is bolted directly to the "+" post of the battery. If the tongue jack does not contain a replaceable fuse, then a fuse should be added along this wire. I SWAG the correct size to be 30A or less, because the insulated wire (and its matching black "negative return" wire) seem to be no larger than 10-AWG.
- - -
Your most likely current issue (the +12V wire path to/from the TM "load center" 12v circuit board) might occur in 3 places:
  1. the funky inside side-mounted battery fuse (it's probably probably a big one).
  2. the long wire from that fuse back to the TM loasd center fuse board.
  3. the smaller ATC fuse supporting that fuse board connection (within the load center).

I don't like that fuse mount, located partway down a narrow side of your fuse box. You can't readily see if the fuse (or breaker) has blown until after you have disconnected the top mount wires and removed the battery. The current wire size from the battery mount is very large, and the fuse must be limited to the smaller wire coming out. (It's probably way to big).

The standard "+12v" wire between the front-mounted batteries and the WFCO circuit board connector is only 10-AWG, and the supporting fuses must not be larger than "30A". If you want to support more than "30A" between the batteries and the rest of the TM (including the power converter main board), then you must upgrade that entire wire to AWG-8 or larger, depending on maximum load which want to allow.

The fuses (WFCO 12v board, size "standard ATC" maybe upgraded to 40A for the case of 8-AWG wire. At the battery, under the top cover, I recommend use of a "maxi" ATC fuse instead of the smaller-legged "standard" types. Fuse holders for the "standard" ones are generally provided with 10-AWG maximum pigtail size anyway, which is not adequate for the larger fuses people sometimes install in error.) Here's a two-pack, you'll need to buy the 40A "maxi" fuses separately (Buy more than one, to have spares.) https://www.amazon.com/VANSIHO-Waterproof-Holder-Copper-terminals/dp/B0B6R8J932/

If you choose to undertake the wire upgrade, I recommend that you change from TM's 'BLACK' insulation color, and buy RD wire instead.
 
I replaced the 30 amp glass tubular fuse just in case even though it looked good, but the flat fuse (20amp) was good so didn’t replace. No change to the situation with electric in the TM which still doesn’t work. Could the brown frayed wires be part of the issue?
 
Lots of detail there, so are you seeing a third fuse , which I believe you referred to as the funky inside side-mounted battery fuse (it's probably probably a big one)?
.
 
Dan in the second pic, yer pointing to what looks like an on/off switch. Is it in the correct position? I think I see a red key.
 
Dan -

Lots of pics, lot of detail, complex area. It is like looking at a knitted sweater, one stitch at a time, and trying to determine what each stitch is doing as part of the whole thing.

Big picture? I think that if we are going to unscramble the situation for you, you are going to have to create a sketch of what is connected to what. You don't have to draw the physical placement of the wires, or their physical routing from one place to another. But the sketch does need to show all the wires, all the electrical connections between the wires, all the dead ends where a wire is not connected to anything, and all the devices (fuses, switches, etc) that are part of the whole. It helps if you indicate the color of each wire in your sketch.

Making the sketch is not hard, but it is painstaking. We have a number of electrical experts on the Forum who can decipher your sketch and tell you how everything works. Help us out here, so we can help you.

Bill
 
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Lots of detail there, so are you seeing a third fuse , which I believe you referred to as the funky inside side-mounted battery fuse (it's probably probably a big one)?

Yes. You are pointing at in 'IMG_9164.jpeg', it connects a thicker battery terminal wire on one side of a fuse (or circuit breaker) to a smaller wire on the other side of the fuse.

That wire is possibly the 10-AWG TM provided "12v" battery connection cable (going back to the WFCO 12v load center fuse board). If so, the 'big fuse' was possibly added as a poorly chosen upgrade.
- - -
Do you have a volt meter? If so, you can confirm 12v voltage from the battery into the into the smaller wire, and check the routing of that wire -- please confirm that it goes back towards the TM fridge area.
 
Repair planning.

DanSTL said:
Thanks Rick will text you now, think you’re in Nevada so maybe not too late? I have a voltmeter and more than happy to have a basic 30A but not sure if it needs to be opened.

Before opening, we can confirm that the TM main wire lug on the existing side-mount fuse/circuit breaker has full battery voltage - demonstrating the the fuse/circuit breaker is not burned out. But we cannot confirm that wire reaches all the way to the WFCO panel circuit board (without breaks or short circuit issues) until after we open the TM and go inside.



If the side-mount fuse/circuit breaker (in the battery box) is "open" (burned out, tripped) we will see zero volts on the TM wire lug, even when the wire has been disconnected. Per a post in the Thread, I strongly recommend that we replace that side-mount fixture with a Maxi fuse and fuse holder (size 30A for standard wirse, size 40A for an upgraded TM wire battery-> WFCO at size 8-AWG).

The side-mount lugs press on the contained battery case at two small pressure points, maybe promoting cracks in the battery itself (and later causing acid leaks and failure). But even more fundamental, It can't be seen without removing the battery from the box. With a small Maxi-fuse inline mount, the fuse lies on top of the actual battery, you can see if it's OK by simply removing the top cover of the box.

If you haven't got a max fuse holder (and matching fuse) with wire leads size 8-awg, you can buy and temporarily use a smaller ATC/ANL fuse holder, they're
available from any auto parts store -- but the wire size of the lead wires will be too small (they're typically AWG-10 at best, AWG-12 and AWG-14 are more typical). In AWG wire sizes, smaller numbers are bigger and better wires.

- - -

If the long wire must be replaced, there may be issues with the current routing. My OEM original (2006) was run along a top corner of the street side frame against the frame, next to the the 7-way bargman cable. It came up into the interior behind the fridge, where it was bundled tight and zip-tied with a large bunch of other wires.

In my own case, upgrading to a much larger wire (AWG-4) required a total re-route within liquidtite conduiit. A portion of the liquidtite conduit is clamped to the bottom of the TM floor. It rises into the TM floor underneath the tub seating area, using a liquidtite connector. But my wire supports a large set of LFP batteries, you don't need all of that capacity.

Your wire replacement issue is this: In the case that the long wire is broken somewhere, the current routing to reach the WFCO panel goes underneath the fridge and bathroom sink, possibly also going inside the lower exterior wall behind the toilet before reaching the WFCO from under the bathtub. There are also probably extra zip ties involved, making it extremely difficult to "pull" a replacement wire by using the existing wire as a part of the pull.

There is some kind of wooden box underneath the sink, that may include wire connections which provide for avoiding the behind-the-toilet wall wire replacement. But I've never looked inside my wooden box, I don't know what is in there.

Primarily for that reason, If the 'long wire' is failed with either a break or a short circuit, I will recommend that we pull its replacement along the frame - past the standard fridge-area wire entry, instead reaching all the way back to the tub area. Those portions of the new wire which can't be clipped to the frame, or other existing clipped cables or pipes, will need to clipped into bottom of the frame. You could use clips like these, as long as the supplied brass screws are replaced by short SS screws. https://www.homedepot.com/p/Gardner-Bender-1-4-in-Coaxial-Cable-Clamp-RG-6-20-Pack-PEC-31525WA/205588202

The wire insulation will need protection at both sharp-edged aluminum hole edges through the floor (at the wire entry under the tub). These box fitting connectors would be OK for wire safety, but do not provide any waterproofing. You could use a good sealant (3M 4200) to provide that at the inside of the fitting, against the foam interior. (As a temporary alternative, a decent indoor/outdoor caulk could also perform that job).

The wire (stranded THHN/THN2) is generally available in 25 or 50 foot packages at big box stores, but only in wire size AWG-10 (not more than 30A). If you upgrade to AWG-8, you must buy by-the-foot and it isn't returnable. In either case, I recommend purchasing with RED insulation color.
 
There is a key, didn’t know but understand it affects power too. Turns out I need a new battery and more…
 
Pics of frayed wire going inside
 

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Nearly everything is now 'resolved'.

(I'll reply WRT to the frayed 12v wires feeding customer-added cigarette lighter ports separately, following this post).

Working together over the phone, we were able to identify the various wires and connected components. In the end, it wasn't too bad - excecpt for the "extra" cigarette lighter connection wires.pe tfor the

The red switch (outside the small side of the box) controls the added battery shutoff inside. The internal connector lug is "closed" with the switch UP, between the TM "main 12v" wire (back to the WFCO) and the larger battery teminal wire.

Voltage on the battery terminals was slightly above 7 volts (a very low value, the battery is damaged and must be replaced). But, with the in-line glass fuse installed in the "Atwood" fuse holder, interior ceiling lights in the TM were usable (although dim). This indicated that the connection between the TM "main 12v" battery wire and the WFCO was good. It also indicated the ground return path (through the frame) to be good as well.

I asked Dan to plug the TM 30A 120-VAC main cord into the house/garage grid, and he was able to do that. We checked voltage at the battery terminals again, and found it to be slightly higher than I like (but not horrible for lead-acid non-AGM batteries). This indicated the WFCO converter mainboard to connected and operating OK.
- - -
I advised that he should probably leave the main cord (30A 120-VAC) connected within the garage in future (to avoid deep discharge during longer term storage). When the battery will be replaced, the cord should be temporarily disconnected only for the battery change.

We talked about battery options a bit, and then quit - calling a success. I still advise that the Atwood glass cylinder fuse holder be replaced by an inline 30A "Maxi" or "ATC" waterproof fuse holder, which can also serve as a shutoff - if he ever desire to have one. A pair of fuse holders is on order, the second for the purposes of replacing the current fuse holder in the 12v red wire to electric jack - the current one exposes the back side of the fuse, it's not sufficiently water resistant. ATC is OK, but Maxi fuses are better - because of the larger legs.

(My issue with glass-lined fuse holders is the spring at the bottom of one end, intended to hold the fuse tight. That spring has been are prone to issues of rust and weakness in many TMs, causing high resistance along the electric path through the fuse - even when the fuse is "good").
 
The badly done "add-in" 12v cigarette lighter ports and wiring.

Pics of frayed wire going inside

The previous owner of Dan's TM had issues with the factory installed 'cigarette ligher' ports - and added a pair of badly done add-in ports, near the microwave area, to augment/replace the factory ports.

TM's cigarette lighter ports form those older model years had two major issues:
  1. The diameter of the socket was too small (narrow) for most plugs to fit in and reach all the way to the "+" pin at the bottom of the socket.postive rrow) Snarrow for a lot of plugs to fit any aul diZAmeter
  2. The units each contained a tiny fuse - extremely hard to replace, and allowing for only small amperage.

The 'upgrade' ports are connected on twin lead "lamp cord" wire pairs, in a confusing way. The upgrade port units are simple, and they do not contain any fuses. They depend of an external fuse to protect the sockets from short circuit, and the prior owner (as far as I can tell) DID NOT put fuses in the lamp cord "+12v" wires back to the battery.

Lamp cord is indoor only, and the insulation is very easily cut. The underside of the TM floor would not be a safe location for such wire, even if it HAD BEEN properly fused. (Wrapping in electric tape is not sufficient).

The cigarette lighter sockets themselves seem somewhat OK, although the grounding terminals are only 1/4" male connectors (rather than screw-down terminals), and the "+" connections were probably made without lugs. For any amount of current above 6A continuous, I prefer to use a high-current twist lock socket with good screw-down wire connections. (Not a mere cigarette lighter "press in" plug and socket combo.) But those sockets and plugs (NEMA L2-20, un-grounded with only two poles) are very expensive. You must purchase and install both the TM socket and the equipment line plug to make it work - and the equipment will no longer be usable with a regular "12v socket".

I have one socket in my TM for such equipment, here's a view of the plug involved: https://www.ebay.com/itm/235192494546
- - -

The current sockets can be fixed for lower current devices (10A maximum, 7A maximum continuous). The routing of the propane powered cabin heater "12v" supply wire (used for the fan and ignition) might run along the lower side wall or floor before crossing underneath the door, that would avoid having twin-lead pairs wires hanging all the way from the front battery box.

But if that's hard to find, then just a SINGLE red leasd should be run underneath the TM floor, and it must be fused immediately following the battery terminal connection (inside the battery box). That fuse should not be higher than 20A for both sockets, and the wire should be 10-AWG.
 
(I'll reply WRT to the frayed 12v wires feeding customer-added cigarette lighter ports separately, following this post).

Working together over the phone, we were able to identify the various wires and connected components. In the end, it wasn't too bad - excecpt for the "extra" cigarette lighter connection wires.pe tfor the

The red switch (outside the small side of the box) controls the added battery shutoff inside. The internal connector lug is "closed" with the switch UP, between the TM "main 12v" wire (back to the WFCO) and the larger battery teminal wire.

Voltage on the battery terminals was slightly above 7 volts (a very low value, the battery is damaged and must be replaced). But, with the in-line glass fuse installed in the "Atwood" fuse holder, interior ceiling lights in the TM were usable (although dim). This indicated that the connection between the TM "main 12v" battery wire and the WFCO was good. It also indicated the ground return path (through the frame) to be good as well.

I asked Dan to plug the TM 30A 120-VAC main cord into the house/garage grid, and he was able to do that. We checked voltage at the battery terminals again, and found it to be slightly higher than I like (but not horrible for lead-acid non-AGM batteries). This indicated the WFCO converter mainboard to connected and operating OK.
- - -
I advised that he should probably leave the main cord (30A 120-VAC) connected within the garage in future (to avoid deep discharge during longer term storage). When the battery will be replaced, the cord should be temporarily disconnected only for the battery change.

We talked about battery options a bit, and then quit - calling a success. I still advise that the Atwood glass cylinder fuse holder be replaced by an inline 30A "Maxi" or "ATC" waterproof fuse holder, which can also serve as a shutoff - if he ever desire to have one. A pair of fuse holders is on order, the second for the purposes of replacing the current fuse holder in the 12v red wire to electric jack - the current one exposes the back side of the fuse, it's not sufficiently water resistant. ATC is OK, but Maxi fuses are better - because of the larger legs.

(My issue with glass-lined fuse holders is the spring at the bottom of one end, intended to hold the fuse tight. That spring has been are prone to issues of rust and weakness in many TMs, causing high resistance along the electric path through the fuse - even when the fuse is "good").


Definitely a success, and appreciate the assist Rick.

Bill at some point will make a sketch as it would certainly help me understand my TM, I found the plumbing sketch very useful.
 
Why not creat and post the diagram yourself?

We already have the basic wiring diagram for older TM models in the library, here: https://www.trailmanorowners.com/forum/attachment.php?attachmentid=18858&d=1584889354

But that is a diagram of the wires, not the physical routing of wires (relative to the TM trailer body). If you know the interior layout of your TM pretty well, then you can guess at the locations for some of those "12v" power wires. Into the curb side of my own TM, there is at least a "12v" power wire leading into the propane furnace, although I haven't checked whether that rise from the floor or routes along the wall. This provides power to the fan, vontrol board, and thye ignitlon circuit). It's shown as a 12-AWG "purple" with a 20A fuse, and it also supports the water pump. Those loads don't have much "free" headroom left to support high current DC-12v devices on the added plug-in ports.

The diagram does not show any electric wires into the oven/cooktop combo which I have, but I seem to remember the stove top burners showing red lamps while running (which might be powered by 12v), and the oven thermostat might also involve a 12v power source.

Maybe just one new fused wire from the battery for those two 12v sockets, although conduit routing will need to avoid the steps (in folded up position, as well as folded down).
 

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