Community Forums

PlanBee · 11-21-2018, 09:24 AM

So I've read a lot of stuff here, learned a lot and hopefully helped others too.

My latest issue has happened twice while the bus was sitting plugged into a power source with the charger on. The first time I thought is might have been a fluke thing, but I stopped at the storage place last night and it did it again, so now I know something isn't right.

Jump in and there is no power from the chassis batteries, which are one month old. The charger panel shows charger is on, 50 or 20 amps 120 VAC coming into the bus. If I push the battery boost button for a quick second, I hear the solenoid in the back of the bus, and then everything is fine. So the batteries were fully charged all along, just not energizing the ignition or anything else.

House batteries were fine.

How does it get disconnected just sitting there, and what am I looking at, the Big Boy Solenoid or the BIRD or something else. I obviously still have some thing I need to understand in this system. Hopefully it does it again so I can look into it and figure it out, but I wanted some insight as to what I should look at if or when it happens again.

Thanks in advance and have a Happy Thanksgiving!

Captjake1 · 11-21-2018, 09:30 AM

I had this happen 2 weeks ago. In talking with one of our senior members who knows a ton about the wiring... It happens from time to time. To re-engage the big boy, push the battery boost button. I did this 2 weeks ago, no issues thus far.
I was advised to get one of those cigarette lighter adapters that shows voltage. When you see voltage (this is on the chassis batteries) dipping, hit the boost button.
No rhyme or reason why it drops off.
There is also a voltage monitor that runs on wifi. Do you can monitor from a smart phone. Handy if your rig sits in storage and you don't look at it daily.

RockyMtnRide · 11-21-2018, 12:50 PM

When I first purchased my 2006 Diplomat I didn’t realize the chassis batteries were not connected to inverter-Charger. Only my house batteries. What coach do you have?

PlanBee · 11-21-2018, 12:59 PM

Quote:

Originally Posted by RockyMtnRide

When I first purchased my 2006 Diplomat I didn’t realize the chassis batteries were not connected to inverter-Charger. Only my house batteries. What coach do you have?

It's an '09 Camelot 42, I'm pretty sure the inverter-charger is connected to the chassis batteries, but I've been wrong more times than I can count. It's been perfectly fine until the last month when I had the two episodes where the chassis appeared completely dead, but just bumping the battery boost switch brings them online and they were actually still at full charge.

RockyMtnRide · 11-21-2018, 01:14 PM

Quote:

Originally Posted by PlanBee

It's an '09 Camelot 42, I'm pretty sure the inverter-charger is connected to the chassis batteries, but I've been wrong more times than I can count. It's been perfectly fine until the last month when I had the two episodes where the chassis appeared completely dead, but just bumping the battery boost switch brings them online and they were actually still at full charge.

Understand. Must be a sticky Interface power relay not working when the BIRD circuit calls for a charge. Might try to disassemble and clean the contacts

Jim McElwee · 11-21-2018, 01:52 PM

I have owned a 05 Monaco knight for 5 years. I had this problem when first purchased. For some reason it went away. Started having problems earlier this year. I replaced the bird and seemed to work. Last week after plugged into 220 volts it came back. Came home and plugged into 110 and start batteries had 10 volts after 4 days. Opened bird lubed, and cleaned and reinstalled yesterday. Will see what it does. Cam someone describe how this system works? Any reply will help three of us. Thanks for each reply.

YC1 · 11-21-2018, 05:29 PM

Here is a likely suspect.

The voltage that controls the solenoid may NOT be going away.

If you can get a measurement on the purple wire that feeds it and also gently touch the solenoid to see if it is warm or even hot.

IF that solenoid is going south for the winter as many do it could act just like that. That is when you hit the aux start button it just might give it a tiny bit of extra kick and then runs for a time.

I would have that solenoid resting on the work bench and a new one in. These are not that expensive and can cause all kinds of crazy symptoms. They may even cause you to have run down engine batteries which could be very costly if the die.

Take the old one apart and inspect it.

Funny, one will replace a fuel filter in an instant but never consider replacing an electronic component unless it is obvious the smoke got out or some other sign of failure.

I have a 2008 Endeavor so suspect our systems are close to identical.

PlanBee · 11-22-2018, 08:29 AM

Quote:

Originally Posted by YC1

Here is a likely suspect.

The voltage that controls the solenoid may NOT be going away.

If you can get a measurement on the purple wire that feeds it and also gently touch the solenoid to see if it is warm or even hot.

IF that solenoid is going south for the winter as many do it could act just like that. That is when you hit the aux start button it just might give it a tiny bit of extra kick and then runs for a time.

I would have that solenoid resting on the work bench and a new one in. These are not that expensive and can cause all kinds of crazy symptoms. They may even cause you to have run down engine batteries which could be very costly if the die.

Take the old one apart and inspect it.

Funny, one will replace a fuel filter in an instant but never consider replacing an electronic component unless it is obvious the smoke got out or some other sign of failure.

I have a 2008 Endeavor so suspect our systems are close to identical.

I have no problem replacing the solenoid.

Just to be clear we are talking about the Big Boy? I already have one in my cart. I just checked on the bus and everything was normal so I couldn’t do any more diagnostics.

Captjake1 · 11-22-2018, 08:35 AM

I had this issue and my Big Boy looked pristine inside.

YC1 · 11-22-2018, 05:12 PM

Mine was two years old or less and when I took it apart it was green and gooey inside. I have taken apart dozens of solenoids and never saw one like this. What a mess it was.

There are hundreds of pages on this forum about those solenoids. Sometimes substitution is just the best diagnostic tool. When in doubt, throw it out.

However, I absolutely hate when people "throw parts" at a problem. Intermittents drive the most experienced technician crazy. Getting decent meter readings when things are running properly is important. I highly recommend taking pictures and then print them out so you can write down reading for future use. A three ring binder is very handy with sheet protectors to keep them in.

Happycarz · 11-22-2018, 08:27 PM

The Big Boy relay requires 12v to engage and 4v to hold the connection. If the Big Boy is "told" by the BIRD to disengage, the BIRD will not send the 12v signal the the BB until it sees charging of 13.2v again. If house batteries are charged, then only 4v is present at the BB hold-in coil. By pushing the Battery Boost switch, you are sending 12v to BB, which re-engages the BB and the BIRD at the same time will continue the 4v hold-in voltage to the coil.

After talking to M & M Electronics, they said to replace the Big Boy. Well, that was a $200 learning experience that did not go well.

The issue is that the battery drops below

Captjake1 · 11-24-2018, 08:08 AM

I noted the chassis batteries slightly lower than the house batteries last night (thanks to the little cigarette lighter voltmeter) . Tapped the battery boost switch and the big boy re-engagd and started charging once again.

YC1 · 11-24-2018, 03:47 PM

Get a voltage reading on the little posts on the relay next time. And also measure the large posts.

If the relay is warm or hot to the touch give the relay a hard smack with the handle of a screwdriver or the handle of a hammer. Then measure the voltages again.

If the large posts are now the same voltage replace the relay.

Barryc737 · 11-24-2018, 10:55 PM

Quote:

Originally Posted by Captjake1

I noted the chassis batteries slightly lower than the house batteries last night (thanks to the little cigarette lighter voltmeter) . Tapped the battery boost switch and the big boy re-engagd and started charging once again.

One word of caution may be appropriate in this situation. I've been communicating with CrazyKnight Craig, the Magnum/battery guru. He schooled me on using the battery boost switch and thinking everything is peachy since you get the engine started. The bad news is that The engine -driven alternator looks at the condition and says "Congrats on getting the engine started, but your chassis batteries are really low and I'm going into overdrive to get them charged." That's one way to burn up the alternator. Workaround would be to start the generator and let IT power the battery charger to recharge the chassis batteries as you drive.