Battery Disconnect Solenoid

[hhornig]

I am helping a friend with a 2008 Jayco Melbourne 29D. He said his battery disconnect switch was stuck and he replaced it. The battery is not disconnected in either the off or on position. I don't know if the prior switch was a momentary switch or and on/off switch. Before I remove the solenoid can anyone provide more information on the circuitry?

[CA_Traveler]

hhornig wrote:
Will get my replacement latching relay monday. Can I do an off-the-coach check?

Yes, use the above wiring diagram to connect and test.

[hhornig]

Will get my replacement latching relay monday. Can I do an off-the-coach check?

[enblethen]

Here is basic wiring diagram.
Wiring diagram

[enblethen]

One way to test the disconnect relay, is to disconnect the wires from the small posts. Keep track of what color went where. Use a two wire jumper or two pieces of wire. Connect them to a battery source. Momentarily touch the small posts. this should activate the relay. test for continuity on large terminals. Then reverse the two wires. touch to small terminals. This should activate the real in the opposite direction. test the large terminals.
The switch should be momentary, it should have six terminals. the two outer posts on each end should have a criss-cross jumper with 12 volts DC connected to one end set. The center two terminals should be connected to small terminals on the relay.

[CA_Traveler]

A latching solenoid has a small second solenoid that will mechanically latch the main solenoid in the closed position. Hence in either position no power is used by the solenoid coil.

[hhornig]

I took out the solenoid which appears to be a latching relay, KIB LR9806. Both fuses were blown. The main terminals had a dead short so there was power to the coach, but no way to turn it off with disconnecting the batteries. My guess is the old stuck switch was a momentary switch and the parts guy provided an on/off switch which when left on overloaded the fuses. The switch was a Sigma LR20985 which appears to be available in several configurations. I am not sure how to test the latching relay. Would it fail in the closed position? Most solenoids I am familiar with fail in the open position.

[dougrainer]

Usually on Jayco, IF the wall switch sticks, it will either burn out the solenoid or blow the fuse at the solenoid. Odds are the Solenoid is bad. Very rare to replace the wall switch. Doug

[enblethen]

everthing is run through the battery disconnect.
Most battery disconnects are operated by a double pole double through momentary switch.
The battery disconnect is normally a mechanical latching relay. When the polarity is reversed the relay is either latched to provide power and unlatched to disconnect.
To be sure, What is make and model of the removed (old) relay?
What is make and model of the operating switch?
Is the switch getting power? Must have both 12 DC positive and negative.