2007 25fb 12V electrical problem

[DonDiego]

We just bought a used 25FB and took it out last weekend. On day 3 the 12V overhead lights were getting dim and the radio would just shut down. We were plugged into the campground 110.
I set the battery disconnect to "Store" and disconnected from shore power and the lights remained on. This is not what I expected as per the manual. Upon returning home, I did the same thing and this time the lights went off when I disconnected from 110 shore power. I also checked the battery voltage and only had 11.1V. I then left the disconnect switch set to "USE" and the 110 plugged in overnight. The batteries were still at 11.1V. I then put a battery charger on the batteries over night at a 2 amp charge. They are now at 12.5V. The batteries are new.
Has the Parallax 7355 converter gone bad? If so, how do I get any 12V?
Thanks for help.

[SteveH]

It sounds like the converter is not charging the batteries, but is providing power to everything else.

I would check to see if there is a fuse between the converter and the batteries, and it's condition.

[dkottum]

I used the Troubleshooting Flowchart from this page to find that my converter was shot.

PPS ESM DLR

doug k

[DonDiego]

Thanks for the info.
Doug, I followed the flowchart test and it indicates all is well and working as it should.
??????? That is the good news, I guess. I am lost as to why the batteries are not charging via the converter. There are no blown fuses etc.

[dkottum]

No expert am I, but a couple things come to mind.

The radio/entertainment system on these models comes on by itself by cycling the store/use switch. Don't ask me why. My radio/entertainment system is hidden behind a cabinet door so I can't see the lights if its on or not. It may be on and draining your batteries.

Are you sure the batteries are new? Or fairly new, maybe only a few years old? Have them checked. Even if near new, they can be bad and not hold a charge, especially if improperly used. The originals in mine only lasted 2 1/2 years.

doug k

[Dakota's Dad]

12.5v is not fully charged. Above 12.6 is. Also, check the charge state of your batteries NO SOONER than 6 hours after removal from charging source. You will just be checking the "surface charge" otherwise. And new is relative.. anytime you let your batteries get below 50% or so, it is very hard on them and shortens their lifespan considerably.

If you let them go down to 11.1.. that's a 100% discharge. VERY bad for your batteries.

EDIT, I knew I had a link somewheres to some good battery info..

[DonDiego]

Originally Posted by dkottum

No expert am I, but a couple things come to mind.

The radio/entertainment system on these models comes on by itself by cycling the store/use switch. Don't ask me why. My radio/entertainment system is hidden behind a cabinet door so I can't see the lights if its on or not. It may be on and draining your batteries.

Are you sure the batteries are new? Or fairly new, maybe only a few years old? Have them checked. Even if near new, they can be bad and not hold a charge, especially if improperly used. The originals in mine only lasted 2 1/2 years.

doug k

Doug, the batteries were new before the weekend trip.
Our radio is out where we can see it and tell if it is on. There should have been no way to have drained the batteries dead being plugged into shore power.
Despite going thru the flow chart, I do not believe we are getting a charge from the Parallax converter. I left it plugged in since yesterday morning and my voltage is still at 12.1V.
Tomorrow I plan on putting the battery charger back on and seeing how much of a charge I can put into the batteries.

[DonDiego]

Originally Posted by Dakota's Dad

12.5v is not fully charged. Above 12.6 is. Also, check the charge state of your batteries NO SOONER than 6 hours after removal from charging source. You will just be checking the "surface charge" otherwise. And new is relative.. anytime you let your batteries get below 50% or so, it is very hard on them and shortens their lifespan considerably.

If you let them go down to 11.1.. that's a 100% discharge. VERY bad for your batteries.

EDIT, I knew I had a link somewheres to some good battery info..

Thanks, I had found the same page/site. I understand what you are saying and agree.
It looks like you have a major redo ahead of you. Thanks again.

[DonDiego]

Here is the latest update.
I believe the converter is working OK. The diagnostic flow chart states, "If the unit has correct DC voltage with "polarity" fuses removed, but does not when "polarity" fuses are in place the converter may be in over current mode. There may be a problem with either the battery, battery wiring, or a connected load. Remove battery (positive) connection at the "C" terminal or one DC load fuse at a time to determine where the problem is. Over current mode is the condition where there is a load(s) connected to the converter that exceeds the current rating of the converter. This can either be a “short” in the coach wiring or just too many things on. The output voltage will decrease as the current exceeds the rating of the converter.”
I removed the circuit fuses one at a time and took a voltage reading for the output of the converter. Doing so, the output did not change. It remained low… 12.1V. I then removed the “polarity” fuses one at a time. With both fuses removed, the output voltage finally increased to 13.5v.
From this I surmise that the converter is going into “over current mode” and that there must be a problem “with either the battery, battery wiring”. Being that the batteries are less than two weeks old, I would guess the most likely cause would be “battery wiring”.
I am unsure what to look for or test for with the battery wiring. Can anyone suggest or guide me thru a test?

[ROBERTSUNRUS]

Hi, just a few things that might help. Make sure your battery connections are clean [wire brushed] and tight. Also as a mechanic since 1968, I learned that "New" doesn't mean good. You may want to have these batteries re-tested.

[DonDiego]

Originally Posted by ROBERTSUNRUS

Hi, just a few things that might help. Make sure your battery connections are clean [wire brushed] and tight. Also as a mechanic since 1968, I learned that "New" doesn't mean good. You may want to have these batteries re-tested.

I agree. I once had a new battery that was bad from the start.
Let me ask, how do I verify the cabling from the converter to the batteries? I cannot do a visual on them other than the connections to the batteries like you have mentioned (and that looks good).

[Dakota's Dad]

Multi meter.. Look for continuity in places it shouldn't be. Disconnect your battery wires from both the battery and the converter, then see how much impedance you have through the cable, and check for grounding by looking for continuity between the cable and ground.. ie: make sure the cable ends are insulated from the trailer, then check to see if there is any "circuit" between a cable end and the frame or ground bar.

I don't know the battery layout of a '07, but on ours, the battery is only 2 feet from the converter.. easy to work on it is.. once you remove the gaucho.

[B and R]

I am not sure whats up. my batteries are less than 1 yo and they were charged on 110. Recently.
When I plugged in to 110 gfi at house the gfi pops off. got 12/2 cable extension cord still pops gfi. tried non-gfi still pops.

I am not sure where the problem. I put the batteries on my charger to get them charges back up.

still, cannot run 110 and not sure if the 7 pin truck.trailer is charging. All lights, signals, brake lights, backup lights work ok.

No blown fuses I can find?

Thoughts please. Thanks

[Al and Missy]

Originally Posted by B and R

I am not sure whats up. my batteries are less than 1 yo and they were charged on 110. Recently.
When I plugged in to 110 gfi at house the gfi pops off. got 12/2 cable extension cord still pops gfi. tried non-gfi still pops.

I am not sure where the problem. I put the batteries on my charger to get them charges back up.

still, cannot run 110 and not sure if the 7 pin truck.trailer is charging. All lights, signals, brake lights, backup lights work ok.

No blown fuses I can find?

Thoughts please. Thanks

You might get more responses with a new thread as it seems your main problem is the gfi popping. What gfi is popping? You said the gfi still pops (trips) when on a non-gfi outlet.

A common cause of gfi tripping is moisture and/or dirt in the box for the outside outlet if you have one.

Turn off the MAIN breaker in your AC panel and see if the gfi still trips. If not, the problem is somewhere in the trailer. If it still trips the problem is with your shore power cord or the connector on the trailer (if you have one) or the wiring to the AC breaker panel from the shore power cord.

You will not get much battery charging from the 7-pin. Typically around 7 amps. If you have a 50A converter the 7-pin will take 7 times longer than the converter, or more.

I can't be more specific without knowing the year and model of your trailer.

Al

[AtomicNo13]

Isnt there a wall mounted switch behind the curtains for the converter?