Blinking 12 volt interior lights

[lekhuset]

Suddenly my lights, that are 12 volt, blink periodically. Trying to narrow it down to when without much luck. We have almost new (1 year old) house batteries. Sometimes the fluorescents hardly come on but there is no specific light. Have checked battery connections and replaced older bulbs. We are plugged in to 50 amp. While watching the Alladin, the battery drops to 12 volts. One time when flushing toilet, the battery dropped to 7 and then back to 12, then shortly after the Alladin showed 13 volts which I assume was charging
like. Does anyone have any suggestions please?

[lekhuset]

Just now the furnace came on, the lights dimmed and furnace almost stopped. We shut the furnace off. Battery is 12.4 volts. ??

[texnet]

Check the output of your converter... the converter most likely serves as your battery charger also. It may have a fuse blown. In a previous travel trailer the converter went bad and the results was the same as what you are seeing.

[rex]

Sounds like the solenoid that is operated by the salesman's switch by your front door is bad. The salesman's switch is used to turn off or on all the 12v dc circuits and while convenient, fails often. Most of us have bypassed the solenoid to eliminate the problem, but that also disables the switch.

The other thing that can cause this is the main battery disconnect switch in your battery compartment. Those also can go bad. You can take it apart and see if the contacts are clean or otherwise OK.

[Mike Canter]

OK, lets use some logic here. First the lights are 12 volts and come directly from the battery and not through the inverter/charger so that eliminates that. The other thing is that the lights are on so we know the salesman switch/solenoid is working unless there are dirty contacts. The clue is is that the batteries are not maintaining the voltage when loads are put on them. This can be a battery failure even if the battery is only one year old. It happens. One bad battery can be maintaining what is called a surface charge so the voltage reads up there but in fact it can be bad when under load. First I would try the obvious and simple things. First check the water level in all the batteries and at the same time check all the connections between the batteries and to the MH including all the grounds make sure they are tight. It maybe time to disconnect those battery cables and wire brush all the contact areas. If all is good then I would take the batteries into Pep Boys, NAPA or Auto Zone and have them all checked underload. Once all that has been checked good then we can go from there and start checking solenoids and things like that.

[lekhuset]

I have checked and cleaned the battery connections. The water was great. I will check it with the hydrometer today. I also will check the salesman switch and the fuse for the converter and others today. It is still going on.
Thanks,
Swede

[Tallyrver]

I had the same type of issue with my last coach, the lights would dim etc.
There was a problem with my Magnum inverter .

The folks at South East Power Systems took care of it.
SouthEast Power Systems
4220 N. Orange Blossom Trail
Orlando, FL 32804
Phone: 407-293-7971
Fax: 407-298-1482
Email: dheisley@se-power
www.se-power.com

Wayne

[texnet]

Originally Posted by Mike Canter

OK, lets use some logic here. First the lights are 12 volts and come directly from the battery and not through the inverter/charger so that eliminates that.

I respectfully disagree. Yes, the lights are 12volts and they do run off the batteries. However, a lot of converters are also used to charge the batteries.

When the converter/charger went bad, in our previous travel trailer, I had the exact same problems. I replaced the converter/charger and all lights stayed bright and the heater worked just fine.

[stubeje]

Mine was the same problem as texnet had. Replaced the converter and problem solved.

[texnet]

Originally Posted by texnet

When the converter/charger went bad, in our previous travel trailer....

Correction... this was in a 2006 Fourwinds Hurricane, not a travel trailer.

After replacing the converter/charger, I took the old one apart and found a cold solder joint on the terminals that were used to attach to the batteries, thus after it was on for a while the connection would break according to the load that was being used. This in turn would cause the voltage at the batteries to drop from the 14.x charge voltage to nominal battery voltage and cause the heater to slow down.

[Pusherpilot]

Mine did it til I bypassed the "Salesman switch" solenoid.
Ron

[Mike Canter]

OK, I reread the initial description of the problem and it does say the MH is plugged into shorepower so it could be the charger. One way to find out is to see if the lights blink or change intensity when not plugged into shore power and the generator is not running. If no AC power coming into the MH then the charger is not in the 12 volt circuit (the inverter is but we are talking 12 volt power). Lekhuset can you please try running the electrics in the MH without being plugged in and no generator. Also, then try it on generator power and see if it still happens and let us know.

[lekhuset]

By bypassing the salesman switch, do you mean to use a jumper from ones side to the other or else remove both sides and bolt them together?

Mike, we will try the disconnect tommorow after dark. It seems the four solar panels are maintaining it in daylight so we have more problems after dark.

Thanks,
Swede

[rex]

Find the solenoid the salesman's switch operates. It is either in your front run bay inside the big fuse box or in your rear run bay depending on what coach you have.

To bypass, remove the large battery cables from each of the large post on the solenoid and tie them together. On some it is possible to just connect both cables to the same post if the post is long enough and the cables reach. If not, remove them both and bolt them together and tape them up real good. That should do it.