Winnebago solenoid/ actuator

[KJ RV]

I’m trying to diagnose the coach batteries on my 2013 Winn Era 70a not charging from the engine while running. (The coach batteries do charge from shore and generator power.)

I tested the solenoid under passenger seat while running engine and it looked like that was the culprit. I had 14+v coming from engine but only 12v on other side. I assumed the solenoid wasn’t working. So I bought a replacement..or the closest thing to it (Cole Hersee 24213 12V 200A Continuous Solenoid).

After the install nothing changed.

So now I’m thinking it’s not getting actuated from the engine running or the ignition on.

Anyone have any insights as to how to diagnose?

Thanks in advance.

[Jon_C]

Check to make sure the coil is getting voltage to activate the solenoid. The 2 small wires on solenoid. If you don’t hear it clunk that’s probably the issue. Look for a blown fuse.

[KJ RV]

Thanks Jon_C..

The two wires going in are the ignition (to charge the coach from the chassis) and the Battery Booster (to give the chassis a boost). I figured out the The Battery Boost works. So I tried the fuse route.

I tested every fuse (both front and back of coach) and they all work. So maybe there’s something between fusebox and solenoid that I’m missing?

.

[Jon_C]

Sounds like a bad connection between the solenoid and ignition.

If you can’t find it you can run a separate fused wire to solenoid from an ignition source.

[KJ RV]

Thanks again...

Just got off phone with Winnebago. I was told this solenoid works (passes curent) with an increased voltage from chassis (when the engine is running).

So, without the engine turned on, the voltage on the inbound solenoid post is not high enough to close (pass current through) the solenoid. It's only when the engine is running (alternator is running and charging chassis battery) and the inbound volts are much higher (14?) that the solenoid then closes (connection made) allowing current to flow to through, thus charging the house batteries.

He went on to say that the only wires going to the smaller post are for the Battery Boost. That works, he states, by allowing a reversal of current, ie the house batteries will charge the chassis battery. Otherwise, this solenoid will not allow current to flow form house to chassis.

I've never heard of this type of solenoid functionality - but I'm calling my local parts place to figure out what the OEM replacement is (I believe Trombetta has discontinued the model that was original to this RV 936-1215-011-21).

[twinboat]

The solenoid does not have voltage sensing circuits. That's always handled by a separate controller.
Some are mounted on the solenoid and most are nearby the solenoid.

Follow the small wire to the controller.

Does the original solenoid have a small control device on it ?

Some use engine oil pressure, from a switch on the engine to activate the solenoid too.

[KJ RV]

thanks for the thoughts @twinboat.

Heres an update.

I contacted Trombetta, the maker of the solenoid. And as everyone suspected, this solenoid works like every other solenoid. The only way to actuate it, is to apply some current to the smaller post. (Not as the Winne rep said by some magical voltage sensing in the solenoid. The Winne rep also said the BB switch reverse the flow of electricity...so that's very wrong as well)

I called Winnebago back as they gave me 100% wrong directions. I was lucky enough to get a knowledgable voice on the other end. He said there is only one wire (set of pos and neg) that connect to the solenoid. They are a yellow (pos) and a white (neg) that originate at the battery boost switch on the dash.

However, he went on to say, is that house battery charging occurs via a wire that can bypass the Battery Boost (BB) switch and piggy back on the BB wire to the solenoid. This wire is powered when the engine is running. So one set of wires, two functions - Battery Boosting and Charging the House Batteries.

I've also heard that the electrical work behind the BB switch can be a bit sloppy coming off the production line. A way to test this is to remove the BB switch on the dash and test the wires and ensure the hookup was done correctly.

Thats my next move.

I should also mention that I can attest to sloppy electrical work, as I noticed that the wiring I saw under the passenger seat did not match the wiring diagram Winne publishes. It was professional but incorrect. For instance, there were both pos and neg wires on the same terminal post.

Anyways, I'll test and report back.