No house power on battery

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Well-known member
Feb 15, 2012
North Florida
Winne 2008 Chateau Class C.... 12 volts on shore power none on battery.  See photo attached... No 12 volts out of the right side of the relay that arrows point to.  Jumper one side to the other and lights are on in the unit.....Tried applying 12 volts to the relay terminals indicated in red nothing happened.  Boost relay on left operates normally...

3 questions for the Guru's:

1. Usually if you apply voltage to the relay terminals the relay should operate (click)  This one does not... Bad relay I assume...
2. Do I need a disconnect relay at all? I never winterize since the girl is used every month and more often in winter? Can I just move the generator cable (red wire with green tape) to the left side as I did the house 12v cable for the trip back home (black wire)?
3. Does this relay stay energized all the time unless aux switch is pushed to disconnect?

Any info would be appreciated and your karma will go up a notch.    8)


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Several possible issues, IN MY CASE the switch that operates that relay was dirty and responded to first step cleaning (remove power, cycle many times, restor power) I should have bought lotto tickets that day.

Bad relay also on the suspect list.  As is the fuse that feeds the aforementioned switch.
Quick answer to all your questions is YES.

The disconnect relay (the one in question) is a mechanical latching relay (solenoid) so if it is already in the activate condition, you won't hear a click.

I suspect it is latched, but the internal contacts are not, making electrical contact.  You can move the large cables to the same side of the relay, or jumper them together with very large cable.  Either method would work.

BTW - when applying 12V to the small terminals to test that particular relay, you must apply voltage to one terminal and ground the other.  The process is reversed to deactivate (and latch) the relay in the opposite electrical configuration.
Jumper the relay with a battery jumper cables and see if that solves the problem. If it does, you know the relay is at fault. Then you can decide to replace or permanently bypass.
Finished our trip with the house power connected to the battery side of the relay . I suspect the relay is bad...

Interesting note, stopped by a dealer for LP on the way home and explained the problem. Tech said the lower part of the converter was bad and replacing it would fix the problem ($350.00). Just happened to have the correct one in the store. I further explained that the old converter had been removed and replaced 6 months ago and checks out just fine.. "Yep, that was definitely the problem you must have installed it wrong..." At that point I did not even buy the LP I was needing and just departed for friendlier territory.

Now back at the lake, I will check it out further and more than likely replace the relay to keep thing working as original.

Thanks for the help

That LP place sounds like a Specialist.. You know the daffynations of "General Practicioner" and "Specialist" in the medical world right:

GP: is a Doctor that treats what you got
Specialist: is a doctor who thinks you got what he treats.

The LP man had a converter for sale, so he said you need it.

Good choice by the way in moving on,  Please notify the DMV in his state of business.

Many years ago I think it was 60 Minutes did a special on rip-off Gas stations,, They had a car with Michigan plates (I do not know why Michiganders are considered best prey but they are) and two guys and their "wives" and kids.. One guy was an Engineer for Ford. (Car was a Ford) the other a reporter.

They had a chase van with a camera crew, disquised,

The filmed the station tossing oil on a xtrut or ice=picking a tire or some such (Assorted stations) one brand name station they pre-viewed the segment for one of their field agents who then requested a phone (This was back before cells) and ... He called for a pump-out truck to empty the tanks, and a sign crew to take down the company owned signs.. That station was done, Right then and there.

DMV got notified too.  The owner got a new job shortly after.
Not all Disconnect  Relays are mechanical latch as I can attest.  My Monaco  Diplomat and neighbors Monaco Windsor used simple relays that required power continuously to keep the relay picked for House Power, no wonder it burns up the solenoid coil.

Bypassed the Relay points and have had no problems since,  I do have the luxury of Shore Power while stored.
This the one installed on my Winnie:
Intellitec BATTERY DISCONNECT RELAY 01-00055-000.

Battery Disconnect provides a simple and safe means of remotely disconnecting batteries of an RV or boat. With a touch of a remote switch, the batteries will be completely disconnected, preventing unwanted drain when the RV or boat are put into storage.
The heart of the system is a unique latching relay developed specifically for this purpose. While this relay is capable of carrying heavy currents, it requires NO power to stay open or closed. It only draws power during activation. The relay is sealed against the environments and is designed to withstand the shock and vibration experienced in the most severe RV or boat applications.

THE RELAY - How it Works
The Battery Disconnect Relay is a mechanically latching switch that operates by the momentary application of battery voltage to the coil terminals in one direction for latching (closed) or the other direction for unlatching (open).
To close the relay, +12 volts is applied to the ""I"" terminal and ground the ""S"" terminal of the relay. When this is done, the plunger is pulled into the coil and the contacts are connected. While this happens, the rod magnet suspended above the plunger is attracted (opposite poles attract) to the top of the plunger by the magnetic field.
When the voltage is removed from the coil, the plunger gets pushed upward by the return spring, but cannot move because the rod magnet is in the way.
To open the relay, +12 volts is applied to the ""S"" terminal and ground on the ""I"" terminal. When this is done, the plunger is again pulled into the coil. However, since the magnetic polarity of the coil is reversed, the rod is repelled (like poles oppose), and swings out of the way.
When the voltage is removed from the coil, the plunger gets pushed upwards by the return spring, breaking the connection between the two large terminals.

There are two 5 Amp fuses for the system, mounted on each relay. Looking at the relay with cap at the top, the fuse on the right feeds the LED indicator and if so equipped, the digital voltmeter. The fuse on the left feeds the power to the switch that operates the solenoid.

Relay Actuation Voltage 10.5 Volts
Continuous Carry Current 100 Amps max.
Short Term Carry Current 500 Amps (30 seconds max.)

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