Trombetta solenoid (battery disconnect)

Bukzin, yes the one under the driver is the Salesman solenoid/switch. Only recently did I bypass mine after accidently bumping the switch leaving the RV. This controls the AC's so they will not turn on and in the event our fur babies are left inside I wanted to sure they could never ever bump the switch.


If you want to learn how the solenoid systems work do a search for BIRD and enjoy reading for hours. Nice to know stuff actually.

YC 1 wrote:

YC 1 wrote:
I own the same rv and am intimately familiar with the solenoid and the operation of the BIRD circuit,.

If you are saying that the voltage on one of the large terminals is lower than the other terminal when there is voltage on the purple wire and 0 volts on the other little terminal then the solenoid is shot and is very common. I have replaced mine twice. I took mine apart to see what the issue was. Green and gooey inside mine. It was only a year old.

They get very hot to the touch so be careful if it has been plugged in a long time.

Order a new one and get the one with silver contacts for better life.

If you want to read all about it for a couple of days I can send you to some very long threads on the subject.

It is a simple dumb relay. Works or does not work. Simple.

To clarify, I am referring to the solenoid in the battery compartment. The same suggestion applies to solenoid in the compartment below the driver. The large solenoid is on the back wall between the battery banks.

And the solenoid up from (under driver) is for the Salesman Switch?

YC1, have you disconnected your Salesman Switch?

YC 1 wrote:
I own the same rv and am intimately familiar with the solenoid and the operation of the BIRD circuit,.

If you are saying that the voltage on one of the large terminals is lower than the other terminal when there is voltage on the purple wire and 0 volts on the other little terminal then the solenoid is shot and is very common. I have replaced mine twice. I took mine apart to see what the issue was. Green and gooey inside mine. It was only a year old.

They get very hot to the touch so be careful if it has been plugged in a long time.

Order a new one and get the one with silver contacts for better life.

If you want to read all about it for a couple of days I can send you to some very long threads on the subject.

It is a simple dumb relay. Works or does not work. Simple.

To clarify, I am referring to the solenoid in the battery compartment. The same suggestion applies to solenoid in the compartment below the driver. The large solenoid is on the back wall between the battery banks.

bullydogs1 wrote:
The trombetta solenoid closes when either the emergency switch is engaged or the generator charges the chassis batteries or the alternator from the chassis is charging the house batteries..The one they use from the factory goes due to corroded connections...replace it with an updated one, (it has a suffix of -20 on it instead of -10)...and then I bet it will work again as it should..right now it looks like it isn't closing to charge the bridge up.

You will notice the OP stated Battery Disconnect, NOT the charge solenoid. That is why I asked him to post a pic. There are 2 solenoids. The Battery Disconnect and the Charge solenoid. I believe he is confused about which solenoid he is looking at, hence the pic I requested. Doug

I own the same rv and am intimately familiar with the solenoid and the operation of the BIRD circuit,.

If you are saying that the voltage on one of the large terminals is lower than the other terminal when there is voltage on the purple wire and 0 volts on the other little terminal then the solenoid is shot and is very common. I have replaced mine twice. I took mine apart to see what the issue was. Green and gooey inside mine. It was only a year old.

They get very hot to the touch so be careful if it has been plugged in a long time.

Order a new one and get the one with silver contacts for better life.

If you want to read all about it for a couple of days I can send you to some very long threads on the subject.

It is a simple dumb relay. Works or does not work. Simple.

The trombetta solenoid closes when either the emergency switch is engaged or the generator charges the chassis batteries or the alternator from the chassis is charging the house batteries..The one they use from the factory goes due to corroded connections...replace it with an updated one, (it has a suffix of -20 on it instead of -10)...and then I bet it will work again as it should..right now it looks like it isn't closing to charge the bridge up.

I believe you are looking at the charge solenoid, that combines the Chassis and Coach battery banks. I have never seen a Battery Disconnect solenoid drop the voltage that much when closed. You are seeing the Coach voltage on 1 side and the chassis voltage on the other. Can you post a pic of the panel/solenoid? Doug

Is there a make and model on the relay?
Many rigs have Intellitec Big Boys as the battery disconnect relay. On some they are held together by three screws. You can take them apart and clean up the contact plate and re-assemble.
Intellitec Big Boy