12v power when not connected to tow vehicle?

[herlihyboy]

We just bought our first camper a few weeks ago (2018 Flagstaff 206LTD). Should we be able to use the dome lights and other 12v-capable things in the pop-up when not attached to shore power or the tow vehicle? That stuff all works when connected to shore power but when we disconnect, it does not. I was thinking the interior light should be usable just from the 12v, even when not connected to our tow vehicle, but we're new...

 

[bikendan]

I hope you have a 12v battery hooked up, on the trailer tongue.
The 12v battery on the tongue provides power for lights, water pump etc.., when there is no shore power.
The tow vehicle only provides a trickle charge to help keep the battery charged.
Your post doesn't mention anything about the popup's battery.

 

[herlihyboy]

Yes, we have a 12v battery on the trailer tongue and it has ~12.5v. From what I can see it has power to the roof lift and from the 7 way plug. I'm not seeing how it supplies power from the battery to the circuit breaker under the camper. I'm not reading any voltage at the circuit breaker under the camper.

 

[TravelSolo]

Do you have a battery disconnect that is in the off position?

 

[reidfo]

Yes, we have a 12v battery on the trailer tongue and it has ~12.5v. From what I can see it has power to the roof lift and from the 7 way plug. I'm not seeing how it supplies power from the battery to the circuit breaker under the camper. I'm not reading any voltage at the circuit breaker under the camper.

Look for a battery disconnect switch. It's generally near the battery.

 

[wmtire]

Besides the battery disconnect, check for a tripped 12 volt DC circuit breaker (usually on frame rail). See this FAQ thread for pics and what you are looking for.

12 Volt DC Circuit Breaker with Manual Reset

Several of the more common asked questions on our forums are "Why don't my 12 volt items work?" or "Why doesn't my battery recharge?" Sometimes this is a very simple fix (as easy as pushing a button) and one of the first things to troubleshoot. The 12 volt DC circuit breaker with manual reset...

www.forestriverforums.com

 

[bikendan]

I'm not aware of any FR popup having a factory battery disconnect switch, especially a 7 years old popup.

OP, what are you referring to when you say "circuit breaker under the camper"?
The trailer fuse/breaker panel will be inside the camper.

 

[herlihyboy]

Here's what I have. Re: the circuit breaker, I have the style in the attached image, but don't see any reset switch on it. It's under the camper near the front. Also, I tested voltage on both posts on the breaker and don't have voltage to / from it.

 

[bikendan]

There should be a 12v resettable circuit breaker somewhere along the A-frame. It will have the tiny black reset button on it, that you press to reset the circuit breaker.
Unless a previous owner removed it.

 

[wmtire]

. Also, I tested voltage on both posts on the breaker and don't have voltage to / from it.

Just to be certain of something...how are you testing for voltage the circuit breaker. If using a multimeter, how are you positioning the probes? I have a reason for asking this.

 

[herlihyboy]

I'm using a multimeter. Red on each of the 2 posts separately on the circuit breaker and then it looks like there's a ground wire right by the breaker that's grounded on the frame so black on that.

 

[reidfo]

I'm using a multimeter. Red on each of the 2 posts separately on the circuit breaker and then it looks like there's a ground wire right by the breaker that's grounded on the frame so black on that.

Since you're not seeing voltage at either pole of the breaker, use the meter's continuity mode to trace the line back from the breaker to see where it connects. Perhaps it is loose or disconnected.

 

[wmtire]

I'm using a multimeter. Red on each of the 2 posts separately on the circuit breaker and then it looks like there's a ground wire right by the breaker that's grounded on the frame so black on that.

Ok great.the reason I asked is you would not believe how many just put the red probe on one side and the black probe on the other side........then never tell us this so we know why they are getting a zero reading.

 

[Aussieguy]

If you follow the wire back towards battery you may just find a switch you didn’t now you had

Many trailers have
battery ——-> disconnect switch ——> breaker ——> fuse panel

 

[bikendan]

If you follow the wire back towards battery you may just find a switch you didn’t now you had

Many trailers have
battery ——-> disconnect switch ——> breaker ——> fuse panel

No battery disconnect switch(see post #7)

 

[Larry-NC]

Okay, let's think about this logically.

The OP reports no voltage between either circuit breaker and what is apparently ground ("grounded on frame").

Possibilities are:
Battery "-" terminal is not connected to ground. (Check -terminal connection at battery, cable, and ground connection)

Battery "+" terminal is not connected to circuit breaker terminal. (Check +terminal connection at battery, cable, and connection at circuit breaker)

Battery is dead. (Check voltage from positive to negative terminal on battery)

By the way, if you are using a digital multimeter, you don't have to pay close attention to where the red and black probes go. If you get them right, it will read 12 volts. If you get them wrong, it will simply read -12 volts. No big deal.

 

[herlihyboy]

Alright guys, I don't think I had a good ground when I was testing the circuit breaker. When I got a good ground, I'm getting voltage on both terminals. So, I have power that far. I think the next step is in the electrical panel. How can I test the power there? The fuses don't look blown to me when I look at them. Thanks for all the help. I appreciate it.

 

[Larry-NC]

Alright guys, I don't think I had a good ground when I was testing the circuit breaker. When I got a good ground, I'm getting voltage on both terminals. So, I have power that far. I think the next step is in the electrical panel. How can I test the power there? The fuses don't look blown to me when I look at them. Thanks for all the help. I appreciate it.

Electrical panel is real easy. Open the cover so you see the fuses (plastic automotive-style, not the circuit breakers. You will see heavy cables, similar to the battery cables.

• One is the battery positive, probably labelled +12. (This the wire coming from of the circuit breaker you looked at.)
• One is the positive wire from the converter (battery charger), probably labelled Vcc.
• And there are two labelled either ground or -12. (They are connected together. One is from the converter. The other is frame ground which is, itself, connected to battery negative.)

So to make the measurement, just measure from the big +12 terminal to the ground terminal.

 

[eric1514]

Alright guys, I don't think I had a good ground when I was testing the circuit breaker. When I got a good ground, I'm getting voltage on both terminals. So, I have power that far. I think the next step is in the electrical panel. How can I test the power there? The fuses don't look blown to me when I look at them. Thanks for all the help. I appreciate it.

Remove and test the continuity of each fuse. There's not that many. Don't rely on what they look like especially if they are still inserted into the fuse block. Sometimes removing the fuse will reveal corrosion on the contact areas.

 

[Aussieguy]

Remove and test the continuity of each fuse. There's not that many. Don't rely on what they look like especially if they are still inserted into the fuse block. Sometimes removing the fuse will reveal corrosion on the contact areas.

the top of each fuse has two little dots .... put the probes on those dots to test continuity
no need to remove fuses to test with a multi meter

you can also clip the negative probe to the fuse panel main negative and place the positive prob on the spot to measure the actual voltage ... use the output side of each fuse and make sure you getting good voltage


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there should be a ground wire connection on the fuse panel
you can test the main ground by using a long extension wire onto the NEG multimeter probe with alligator clamps and then the extension to a good frame connection.

I actually run my extension wire under the bed and then to battery (battery is under bed)

then other probe is used to put on the fuse panel negative ... there should be continuity
zero OHMs on meter... looks like a horse shoe on the meter's function selector


IF NOT zero
remove he whole power panel from the wall you should see a negative bus bar with a rats nest of all the appliance negatives connected to it
and ONE main negative disappearing into floor (or wall) and then to another frame ground connection

Find the frame ground connection and make sure it is good and tight
make sure they remover the paint off the frame so wire lug has good electrical connection
remove any star washer between frame and lug too

my fuse panel ground connection to frame was in the under belly........... but at a joint
so I could pulldown just a portion of the underbelly, but still a PITA to work on

should have re-wired it so it goes to the outside of the frame
Just would have needed to drill another hole in the floor then could bolt the negative to the outside of the frame for easier future inspections