Boost/charging solenoid quit

RSteele · 06-12-2016, 11:05 PM

Winnebago owners, this is my second Winne DP that has had the boost/charging solenoid stop working. Searching on the forum I noticed that this is a common problem so I'm posting to hopefully make someone's head scratcher easier. There is a fairly long detailed post from about 8 years ago on the same issue. The battery boost switch on the dash will obviously connect the house and engine battery banks together for added power when the engine batteries are low or its cold outside it will help turn the engine over faster. The same solenoid also and more importantly lets the engine alternator charge the house batteries while you are driving. You wouldn't automatically know there is a problem because everything will work fine unless you are using the inverter or other power drains while driving and the coach batteries all the sudden are low or dead. So to test for this start the engine with the coach unplugged, generator off, then press the battery monitor on the one place. The engine and the coach batteries should show near the same voltage mine is 13.8 but it should be somewhere in the hi 13's close to 14. If your coach batteries are not charging but the engine batteries are the solenoid is most likely bad. You can press the boost button 4-5 times rapidly and it will sometimes knock the oxidization off the contacts and start functioning again. Mine will not. The root cause according to people more knowledgeable than I is that the solenoid is 12 volt and the alternator puts out close to 14 volts. This apparently heats up the contacts causing failure eventually. The solenoid is manufactured by Trombetta 114-1200-010. There is an upgraded version of the same thing it has silver contacts instead of copper and will last longer. It is $49 on Amazon if you go through Winnebago parts I was quoted over $100. Not sure all coaches the new coaches have the same system but my 04 Journey and 07 Vectra do. On the Vectra it is in the last baggage compartment on the passenger side right in front of the A/C unit behind a metal cover on the left side, it is labeled. On the Journey It is in the very front of the coach behind the hood in a metal box. There are two solenoids on both coaches the smaller one is the coach battery disconnect solenoid, it has smaller wires going to it to tell them apart. The boost/charging solenoid has large battery cables going to it mine are 4/0 coming from the coach batteries red in color black coming from the start batteries probably 1/0 size. The boost solenoid is also the place to connect your trickle start if you don't have one. My 04 did not and I added it best $40 upgrade I did to it. Now the same company makes the ampl start which is a charger/maintainer whereas the trickle start is just a maintainer and supposedly won't charge from dead. There are probably others too. Easy to hook up 3 wires and good instructions included. The 07 Vectra has one installed from the factory. Somewhere between 04 and 07 Winne started installing this feature. For those that don't know the trickle start is just a small box that takes a little power from the coach batteries when they are charging and gives it to the start batteries so they are always topped off and ready to go. Easy to test solenoid if you have a meter. Start coach measure voltage on the small pins on the solenoid with engine running small posts should have alternator voltage up near 14 volts, this tells solenoid to close and bridge the two battery banks, yellow wire should be + white should be -. Test engine side batteries smaller set of wires on big posts should have near 14 volts. Test coach battery side should have same as engine side if solenoid is working if lower solenoid is bad. When you go to change the solenoid disconnect coach battery "out" wires and engine battery wires. It may only be 12 volts but there is a lot of amperage coming from those batteries. You do not want to touch any metal with them there will be sparks better to disconnect the batteries and be safe, you can be injured. Remove any jewelry especially rings when working with electricity, I know a man that almost lost a finger because if a wedding band and a 12v battery bank. You can weld with that much current so I can't stress disconnecting the batteries enough. I see you can lower the voltage going to the solenoid coil by using resistors or diodes but I'm going to install it as it was, it lasted almost ten years so I will hope for another 10 out of this one. There are other manufacturers like blue sea systems that make alternatives but at $160 I'm going to use the factory replacement and not have to worry about changing anything. If the new solenoid doesn't last I may go with a more robust replacement such as a blue sea systems unit. Hope this helps someone, it's been a learning expieriance for me.

Duner · 06-13-2016, 05:12 PM

Here's another solution that Winnebago uses in the new big models that have 6 AGM house batteries. It's a very beefy unit.
You can buy it here for $155: HERE It does a lot more that just connect the chassis/coach batteries together.

RSteele · 06-13-2016, 08:26 PM

I was wondering if Winne ever made a change for better reliability. I'll have to look into that. If it has the same connections that would be great. Thanks for that. Did you install one?

RSteele · 06-13-2016, 09:34 PM

I was wondering if Winne ever made a change for better reliability. I'll have to look into that, thank you for the info. Did you install one? I looked up the website. The battery isolater sounds great but I will have to run another wire as it has separate terminals for ignition and the boost button. Currently my coach only has one wire for ignition and the boost button. Not sure if you could just use the same wire for both terminals. Being that it is semi smart not sure if it will work right if some of the terminals aren't used. More research required.

Shuffster · 06-13-2016, 09:38 PM

On a Journey that I previously had, I found it quite simple to open up the solenoid and clean the contacts. Took about an hour. (Take it off the MH and to your work bench.)

Duner · 06-13-2016, 09:43 PM

Yes, I bought one and installed it myself 1.5 yrs ago. Since I installed $1100 worth of AGM batteries, I didn't want the agm's overcharged by the engine alternator on day long runs (they are less forgiving than wet cells). This device will monitor the bat volts and charge only as needed. And it's a very beefy solenoid.

Another fix, if you've got more time than money......
The original solenoid quit after about 3 yrs of ownership and I took it apart to fix it. I cleaned and filed the copper contacts and flipped over the copper washer that was badly pitted on one side and put the fresh new smooth surface to make the contact connection. The outside case is fairly soft aluminum and easy to pry open and bend back to re-seal. It then worked fine for another 7 yrs. I did change the technique when using the "Bat Boost" function tho. I would toggle the switch 2-3 times before holding in down. Being an electronic engineer for 40 yrs, I've seen many switches fail because of dirty and/or contaminated contact surface. So when you arc the contacts a few times it tends to blast off the surface contamination. I think my theory worked, since the solenoid was still working when I pulled it out after 7 yrs. It's in my spare parts box now.

FIRE UP · 06-13-2016, 10:19 PM

Well gang,
I too have had issues with that infamous solenoid. It originally lasted 11 years. I figure that's pretty good based on some of the reports on here. Some say theirs lasted only 3-4 years from new. Well, I too figured what the heck, lets dissect this thing and see what the innards look like. When it was completely apart, it appeared as though it was barely used. No real hard or large carbon deposits at all. But, me being me, I cleaned everything up anyways.

I bolted it all back together and, it worked as good as new. That was about 1.5 years ago. Well, we recently left on a trip for points north and, low and behold, it quit working again. Well, at an Elks Lodge campground in Ridgecrest CA, I yanked that solenoid again and, again, it looked as though it had almost never been used. So, again, I cleaned things up and, re-installed it. Again, it's now working flawlessly.

But, how long will this recent cleaning last? Who knows? I may just bite the bullet and procure a new one. We'll see.
Scott

bobmac · 06-13-2016, 11:08 PM

I have replaced mine twice. The problem causing the failure on mine was pitting and carbonization of the internal contacts as a result of arcing. Rebuilt the old one and now carry it as a spare. If you a residential fridge, solenoid failure becomes problematic as you cannot run the fridge while travelling without using the generator. Looked for but couldn't find the silver contact unit - will have to look again. Good and helpful post RSteele!

tombones49 · 06-14-2016, 05:33 AM

I would like, (need), to join this discussion. 2004 Winnebago Brave, 32V on Workhorse chassis, 8100 Vortex engine. All seems well on landline power or when using the Onan gold 5500 generator. Batteries are deep cycle and one year old. Coach now has all LED lights and it only cost one arm and better, only one leg. The 12v lights don't turn on when using the coach batteries. I have toggled the Coach Battery Disconnect switch with no improvement I removed the top step plate for battery access and then the top kick plate to get to a 12v reset button panel.

Winnebago Tech Rep told me where the panel was or I would have never known it even existed. The BATT disconnect switch seems to have quit working according to the Tech Rep. So I got a new switch. That was no help. Then the Rep directed me to the disconnect solenoid and the related relay. Now the Rep says the solenoid is bad. $60 later a new solenoid did not fix the problem either. I think the Tech Rep is really just a kid who can spell 'solenoid' correctly. By the way, no reset buttons were tripped on the kick plate panel or on the main 12v panel behind the sink and next to the staircase.

I hear no clicking sounds when toggling the Batt Disconnect switch OR when toggling the Battery Boost switch. All connections, including battery cables, are clean and tight as are connections at the 12v panels. "HAVE VOLTMETER, WILL TRAVEL." Any help out there guys? >> P.S. The Tech Rep's prior job was flipping burgers, "Ya want fries with that?"

YC1 · 06-14-2016, 05:56 AM

Tombones, if you are positive about which solenoid is supposed to control the circuit just put the voltmeter on the small leads and tell us what you see. Measure from ground to each of the small terminals. Do the same on the large ones. You could have easily blown a fuse while changing it and just have a new self inflicted wound.

tombones49 · 06-14-2016, 06:38 AM

About 7:30am in New Jersey now. I can do some checking in a couple of hours. I'll check all known fuses and reset buttons then use the voltmeter to check the leads on the solenoid and adjacent relay and get back to you. My understanding of the system is that the coach batteries can be disconnected from the coach via the BATT DISCONNECT switch. This stops any drain during storage periods. Also, the BATT BOOST switch momentarily assists the chassis battery to start engine (if needed), but also serves to allow the coach batteries to be charged by the engine even if the Disconnect switch is activated. Right? Wrong?

RSteele · 06-14-2016, 09:20 AM

There is a small blade fuse on my battery disconnect solenoid, does yours have this? Could be blown when changing solenoid. Voltmeter is you best friend. Maybe a dumb question, are the batteries charged? It's usually the small things that leave you scratching your head. I had a fifth wheel some years ago that all the sudden had no power to the refrigerator. I tested everything I could, and most other lights and appliances worked I was stumped and getting ready to leave on vacation. I went and sat down with an adult beverage and pondered. Then the lightbulb came on in my head. My 4 year old had been helping me inside. He must have pushed the test button on the gfci plug by the entry door as it was at his level. I reset the gfci plug and all was good again. Not saying your gfci plug is the problem cause it's 120v but it's usually the "if it was a snake" things that get ya.
Duner..... What did you do with the extra terminals on the precision circuits unit? I.e.; generator terminal, boost and separate ignition terminals? I'm thinking about going that route but would prefer not to run a bunch of new wires if possible. I can live without the boost portion, have never needed it. If it came down to it I could jump the banks with cables if needed.

tombones49 · 06-15-2016, 05:27 AM

The Battery disconnect solenoid has no blade fuse but the Relay next to it does. It ended up that I couldn't work on the RV yesterday, (or today). Tomorrow is dedicated to the RV. The wife and I are camping this weekend. I'll let ya'll know what I find.

RSteele · 06-15-2016, 09:14 PM

Fire up.... How are you getting the solenoid apart? I drilled the rivets out, desoldered the small contacts and removed the coil. It's pretty dark but it was still clicking when I removed it just didn't transfer power. I suspect the contacts need cleaning but how do I get to them. I'm thinking I have to remove the posts. If I put two nuts on the post will this allow me to remove the top posts and get to the contacts? I did notice something after I installed the new solenoid. When I first start the coach the solenoid will click in and out for a couple of minutes at low idle. I believe because it was about 65 outside and the engine was cold the intake heater draws enough amps at low idle it causes the solenoid to cycle. The Cat C-7 has a similar intake grid heater that pulls a lot of amps also. Normally the engine would go to high idle by itself in these conditions but I hit the brake pedal because I didn't want to listen to it at high idle while I was working on it.

Duner · 06-15-2016, 09:27 PM

Here's what mine looked like taken apart. Use a small screwdriver to pry the crimp open around the circumference of the lid.

RSteele · 06-16-2016, 09:21 AM

I have a different type of solenoid. All the guts come out the bottom. Housing is plastic. I'm thinking the top posts unscrew to drop the contact plate out the bottom.

YC1 · 06-16-2016, 04:04 PM

Here is the Trombetta relay opened.

YC1 · 06-16-2016, 04:07 PM

Rsteel, was your relay mounted with the large terminals up or down? I believe that mounting them with the large terminals down allows condensation to collect and cause the contamination shown.

RSteele · 06-17-2016, 09:19 AM

They were mounted up. Thanks for the picture. Maybe I just didn't bang on it hard enough or its really bad inside? The contacts just will not come out of it. I tossed it in the trash. If this new solenoid goes bad I will change it out to higher priced unit, precision circuits or blue sea systems.

FIRE UP · 06-20-2016, 11:11 PM

Quote:

Originally Posted by RSteele

They were mounted up. Thanks for the picture. Maybe I just didn't bang on it hard enough or its really bad inside? The contacts just will not come out of it. I tossed it in the trash. If this new solenoid goes bad I will change it out to higher priced unit, precision circuits or blue sea systems.

RSteele,
I'm incredibly sorry for not getting back here to answer your question on how to dissect the solenoid. We've been on a trip and have not had good internet during it. I know you've tossed yours but, just in case anyone else is watching this thread, once the rivets are drilled and, the solder points are de-soldered, yes, it can be a bit of a pain to actually separate the moving parts. It's just a tight fit, that's all there is to it. I've pried a bit with a tiny screwdriver and it finally gave way. It was a bit illusive but, I won.

My contacts in mine looked like it was installed the day before I dissected it. But, I cleaned them anyways. It's worked now for about 1.5 years or so. But, it's now acting up again. Well, it's time to look for a new one.
Scott