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jadtif · 08-27-2016, 05:49 PM

We have a 2016 Forest river microlite 25' trailer. I have developed a problem with the 12v system. The problem is that the battery will not always charge when pluged into 120v. It is a intermittent problem. I can hear the converter fan run at times. The battery has 12.6 volts and is fully charged but it will not run the 12v. lights or electric jack without either being plugged into 120v. or into my pickup truck. My questions are 1.) Does the converter alway put out 13.5v. to the battery when connected to 120v.? Sometimes I see 13.5v. at the battery and other times not when plugged into 120v. 2.) If the battery is fully charged why wouldn't it power up the 12v system, but my 12v from my pickup truck powercord will? I have checked fuses but possibley there is a lose connection somewhere. Not sure if the converter has a seperate charging feature seperate from providing the 12v. in the cabin when connect to 120v. Of course the unit went off warrenty last month.

okcnewbie · 08-27-2016, 06:24 PM

The fact that your battery will not run the lights is interesting. Even a discharged battery would turn a light on.

You need to have your battery tested. It may show 12.6 but not really be good.

To be properly charged most converters will get up to about 15 volts at times.

I highly recommend that you install a proper battery meter like the Trimetric. It's fairly expensive but will help you keep an eye on everthing from the converter to the alternator.

bigchick · 08-27-2016, 06:26 PM

doesn't make sense. you can run the 12 volt stuff from either the 120 through the converter or from your truck. so it sounds like the 12 volt wiring and fuses are ok. but you say that the 12 volt stuff will not run from your batteries. so first thing i'd look at, are the batteries actually connected. have you checked the terminals and the battery cables for corrosion? even if the batteries are charged (which I assume you measure from the posts) they will not supply power of the terminal or cables are broken or corroded. you state that you get a reading from the converter at the battery. again a bad cable connection could allow voltage across it while limiting amperage. thus you might see some volts but there is not enough current flowing. similarly, a charged battery will show volts on its post but bad cable connections will limit the amps flowing out of the battery. I don't claim to be an expert but i'd sure be looking at the battery cables and connections.

parkerbill · 08-27-2016, 06:43 PM

Quote:

Originally Posted by bigchick

doesn't make sense. you can run the 12 volt stuff from either the 120 through the converter or from your truck. so it sounds like the 12 volt wiring and fuses are ok. but you say that the 12 volt stuff will not run from your batteries. so first thing i'd look at, are the batteries actually connected. have you checked the terminals and the battery cables for corrosion? even if the batteries are charged (which I assume you measure from the posts) they will not supply power of the terminal or cables are broken or corroded. you state that you get a reading from the converter at the battery. again a bad cable connection could allow voltage across it while limiting amperage. thus you might see some volts but there is not enough current flowing. similarly, a charged battery will show volts on its post but bad cable connections will limit the amps flowing out of the battery. I don't claim to be an expert but i'd sure be looking at the battery cables and connections.

+1 on checking the battery connections for corrosion and good contact.

Rockwood27 · 08-27-2016, 06:50 PM

Do you have a battery disconnect (salesman) switch that is shut off?

powercat_ras · 08-27-2016, 07:01 PM

Follow the positive battery cable, chances are it goes to a terminal block mounted on the frame below the front cap. This is NOT just a terminal block, it has a circuit breaker integrated into it. The feed to the DC side of the Converter and it's fuse panel goes thru this circuit breaker. It has a little plastic button on it that pops out when tripped. You may have to clean it to see the button and operate it, chances are it's mounted under the RV where it gets exposed to the elements. Look for it and push it back in. Had this on my 23 foot Heartland Edge and it would trip occasionally, this was more than just annoying as it causes the fridge to stop cooling even on propane when not getting 12 volts from the Truck or the AC-DC converter.

These are cheap circuit breakers not really designed to be mounted in the open like the RV makers do, and as a result are failure prone. You can replace this circuit breaker with a fuse holder and fuse. For your TT a 40 amp fuse should do.

nothermark · 08-27-2016, 07:03 PM

+1 on the battery disconnect. Look for a can type relay connected to the + battery terminal. That is your disconnect relay. Find the switch that controls it. The converter puts out around 13.6 or more volts. You should see that on both sides of the relay when it is closed. If you see different voltages on the two big terminals the relay is open. I'd get that sorted out before I did anything else. YMMV.

Rorytug · 08-27-2016, 07:49 PM

+ 2 on the battery disconnect switch. When it is off everything will still run on 120 short power. But the batteries will not charge and when you disconnect nothing will work if the switch is turned off. I can't imagine corrosion type problems on the 2016 coach.

jadtif · 08-28-2016, 05:30 AM

Quote:

Originally Posted by Rorytug

+ 2 on the battery disconnect switch. When it is off everything will still run on 120 short power. But the batteries will not charge and when you disconnect nothing will work if the switch is turned off. I can't imagine corrosion type problems on the 2016 coach.

There is a switch and a 30a fuse under the battery on the frame. The switch is closed and the fuse is good. I should take a continuity test of the switch to see if it is operating and not assume it is good. The unit looks like new and everything is free of corrosion.

Rorytug · 08-29-2016, 10:35 AM

Quote:

Originally Posted by jadtif

There is a switch and a 30a fuse under the battery on the frame. The switch is closed and the fuse is good. I should take a continuity test of the switch to see if it is operating and not assume it is good. The unit looks like new and everything is free of corrosion.

I am not familiar with TT's so I don't know if they routinely have a battery switch or "salesman switch" as some call them. However, if equipped, it would be on the interior. Usually by an entrance door. It is usually a rocker switch. On my Motorhome, it looks like this. Check high and low around doors.

The converter converts 120 ac to 12v DC a well as charges the battery. You will hear the fan run as it gets warm when powering the coach, even when it is not charging batteries.

Rorytug · 08-29-2016, 10:50 AM

Quote:

Originally Posted by Rorytug

I am not familiar with TT's so I don't know if they routinely have a battery switch or "salesman switch" as some call them. However, if equipped, it would be on the interior. Usually by an entrance door. It is usually a rocker switch. On my Motorhome, it looks like this. Check high and low around doors.

The converter converts 120 ac to 12v DC a well as charges the battery. You will hear the fan run as it gets warm when powering the coach, even when it is not charging batteries.

I didn't see my picture pop up so I'll try one more time.

1bigmess · 08-29-2016, 10:54 AM

Quote:

Originally Posted by jadtif

... electric jack ...

This makes me think the problem is at your battery, or the battery itself, or both. On my trailer, the positive lead for the electric tongue jack goes straight to the positive on the battery, and the jack uses chassis ground. If your trailer is the same, you've at least got a problem right at the battery.