Coach battery not charging when driving

morles · 10-19-2016, 05:37 PM

I have a 1999 Winnebago Adventurer diesel pusher and when I'm driving it the coach batteries are not charging up.
Any Ideas where to start looking?

rskeans · 10-19-2016, 05:39 PM

There is probably an in-line fuse somewhere. Start checking fuses.

krivanj · 10-19-2016, 07:39 PM

This happened to me this summer and happened to the former owner of my coach. Both times it was connections that had loosened to the batteries over time.
At least it is an easy thing to check. Also check the connection at the back of the alternator. At least on Fleetwood, alternator goes to batteries.
You can put a meter on the alternator to make sure it is working too.

JoeSR · 10-20-2016, 08:09 AM

I share your problem.

Earlier this summer my coach batteries were not charging when the coach was plugged into shore power. I found 7 loose 12V connections. 3 of those were directly related to my problem. My coach batteries are now being charged when the coach is connected to AC power. Also, my stairs extend and retract smoothly (one of those other loose connections went to the stair motor).

Now, after a month long trip, I discovered that my coach batteries are not being charged while I drive. I believe that my connections are solid, but will recheck with a wrench and a volt meter. Also, per the Winnebago wiring diagram, there is a battery isolation relay between the generator and the coach batteries. I will be checking this first.

One word of caution. Before you put a wrench to any 12V connection, disconnect your batteries from the circuit.

John Hilley · 10-20-2016, 10:58 AM

More than likely it is the battery isolation solenoid, a very common failure.

FIRE UP · 10-20-2016, 11:58 AM

Quote:

Originally Posted by morles

I have a 1999 Winnebago Adventurer diesel pusher and when I'm driving it the coach batteries are not charging up.
Any Ideas where to start looking?

Well Sir,
The very first thing you need to do is, learn how your coaches charging system(s) work. That is, just exactly how do both sets of batteries, coach and chassis, get their charge, when the engine is running? And, just exactly do both sets, get their charge when plugged into shore power? You see, in many, many Winnebago and Itasca products for years, DID NOT charge the chassis batteries when plugged in to shore power. There are aftermarket remedies for this that are easily installed.

As for the charging of your coach/house batteries while driving, there may certain components involved that have gone faulty. As one poster has stated, it's possible the "Auxiliary Start Solenoid" has failed. That solenoid, if you have one ( I hesitate to say whether you do or not, based on your year but, you most likely do), has dual duty. In that, if your engine batteries have fallen below the required voltage to start your engine, you should have an "Auxiliary start" button or toggle, on your dash some place. When you push that toggle/button, you engage a heavy duty solenoid that connects the house/coach batteries with the engine batteries, to provide additional voltage/amperage to assist in starting the engine.

Now, once you let off that toggle/button, the solenoid will disengage. But, if it's wired as many of ours are, that solenoid will re-engage once the engine is running. When that happens, it will link the charging of the chassis batteries to the house batteries. Now, both sets are being charged while your driving down the road.

So, while suggestions have been made to check your terminals on the batteries, which may be a good idea, based on periodic maintenance anyways, one of the first places I'd check is, to see if you have this solenoid that I'm speaking of and, to check it's operation. The first thing here is, again, if you have that auxiliary start switch on the dash, leave the engine off, and push that toggle/button and listen for the "click" of that solenoid, where ever it is on your coach. If you hear it, that means it's working.

But, that doesn't mean IT'S WORKING. Sounds kind-a odd doesn't it? What I mean by that is, that solenoid can make the click sound as though it's engaging and, in fact is, if it's making the click sound. But, that doesn't mean the contacts inside the solenoid are making good contact, enough to transfer high voltage/amperage across the them for battery charging purposes. Many of us have heard the click but, when checking for a charge to the house/coach batteries, there is NONE.

A voltage check on each side of the solenoid terminals before and after, you push the auxiliary start button/toggle will reveal certain results. And, the same test, before and after the engine is started, will also reveal certain results. Let us know what you find out.
Scott

twinboat · 10-20-2016, 12:24 PM

Many MHs of that era used solid state Battery Isolators. Google for a picture.

The builder would direct the alt output to the diode isolator and send the charge current to both sets of batteries.

There would be no coach to chassis charging with them. Only dual charging when engine is running.

Find what type of system you have and report back.

krivanj · 10-20-2016, 12:52 PM

When the op said coach batteries I thought he was talking about chassis batteries. If he is talking about house batteries, the isolater makes sense.

morles · 10-22-2016, 09:11 PM

Quote:

Originally Posted by FIRE UP

Well Sir,
The very first thing you need to do is, learn how your coaches charging system(s) work. That is, just exactly how do both sets of batteries, coach and chassis, get their charge, when the engine is running? And, just exactly do both sets, get their charge when plugged into shore power? You see, in many, many Winnebago and Itasca products for years, DID NOT charge the chassis batteries when plugged in to shore power. There are aftermarket remedies for this that are easily installed.

As for the charging of your coach/house batteries while driving, there may certain components involved that have gone faulty. As one poster has stated, it's possible the "Auxiliary Start Solenoid" has failed. That solenoid, if you have one ( I hesitate to say whether you do or not, based on your year but, you most likely do), has dual duty. In that, if your engine batteries have fallen below the required voltage to start your engine, you should have an "Auxiliary start" button or toggle, on your dash some place. When you push that toggle/button, you engage a heavy duty solenoid that connects the house/coach batteries with the engine batteries, to provide additional voltage/amperage to assist in starting the engine.

Now, once you let off that toggle/button, the solenoid will disengage. But, if it's wired as many of ours are, that solenoid will re-engage once the engine is running. When that happens, it will link the charging of the chassis batteries to the house batteries. Now, both sets are being charged while your driving down the road.

So, while suggestions have been made to check your terminals on the batteries, which may be a good idea, based on periodic maintenance anyways, one of the first places I'd check is, to see if you have this solenoid that I'm speaking of and, to check it's operation. The first thing here is, again, if you have that auxiliary start switch on the dash, leave the engine off, and push that toggle/button and listen for the "click" of that solenoid, where ever it is on your coach. If you hear it, that means it's working.

But, that doesn't mean IT'S WORKING. Sounds kind-a odd doesn't it? What I mean by that is, that solenoid can make the click sound as though it's engaging and, in fact is, if it's making the click sound. But, that doesn't mean the contacts inside the solenoid are making good contact, enough to transfer high voltage/amperage across the them for battery charging purposes. Many of us have heard the click but, when checking for a charge to the house/coach batteries, there is NONE.

A voltage check on each side of the solenoid terminals before and after, you push the auxiliary start button/toggle will reveal certain results. And, the same test, before and after the engine is started, will also reveal certain results. Let us know what you find out.
Scott

Hi Scott
Thanks for all the valuable information you sent. I do have two solenoids in the electrical system. One is the Battery disconnect with two large connections for the heavier wire and it also has two smaller terminals which I can't seem to get a voltage reading off them no matter what I do. It also doesn't have an audible click but the other solenoid in parallel with it does have an audible click. They say that there is suppose to be a fuse in the system for this but I haven't been able to isolate it but have found one badly corroded wire but after cleaning it up, it still didn't work. I will get back at it tomorrow and measure the voltages at all terminals with the switches in the different positions.
Thanks for your info on this
Les

morles · 10-22-2016, 09:16 PM

Quote:

Originally Posted by rskeans

There is probably an in-line fuse somewhere. Start checking fuses.

Thanks I have looked for that fuse and cannot find it

FIRE UP · 10-22-2016, 10:35 PM

Les,
You're most certainly welcome. I cannot tell you if there's a fuse for that particular part of the charging system or where it could possibly be as, I've not had a reason to look for it myself. I've only had an issue with that solenoid I spoke of and, rebuilt it once, it lasted for about a year and, went kaput again so, I chucked it and purchased a new one with Silver contacts. If you do find a fuse that helps control that system, let us know so that we all can learn.
Scott

l1v3fr33ord1 · 10-23-2016, 05:09 AM

morles-

If you haven't already done so, download the wiring diagrams for your coach from this link.

Looking at the set for the "1999 Adventurer/Suncruiser G34V Wiring Diagram Book," pay particular attention to the "Body, 12V Wiring Diagram" and the "Automotive Wiring Diagram." On the latter there are three different chassis in the same drawing set: Chevy/GM, Ford and "FL," presumably "FreightLiner."

It appears that (as the coach came from the factory) there is no connection between the two battery banks unless the AUX START switch on the dash is pressed.

My reading was superficial and could be incorrect, though.

winnie32v · 10-23-2016, 05:42 AM

OK, I'm not that good at reading wiring diagrams, BUT, could anyone advise me on:

2001 Winnebago Adventurer 32V,

I am not aware that my coach batteries are charging when I am driving the unit. IF I AM supposed to have a Coach Charging System, could someone tell me AND where to look for the solenoid so I can check it.
I have to charge my Coach Batteries using the generator when I am getting a low voltage reading. Usually after I stop at night after driving for 2 days. I can only assume that the coach batteries are not charging when I am driving or they would be at peak voltage. I do have a factory solar charger on the roof and the red charging light is on.
So, please advise if you can help me.

Thanks for your time.

twinboat · 10-23-2016, 06:32 AM

Quote:

Originally Posted by winnie32v

OK, I'm not that good at reading wiring diagrams, BUT, could anyone advise me on:

2001 Winnebago Adventurer 32V,

I am not aware that my coach batteries are charging when I am driving the unit. IF I AM supposed to have a Coach Charging System, could someone tell me AND where to look for the solenoid so I can check it.
I have to charge my Coach Batteries using the generator when I am getting a low voltage reading. Usually after I stop at night after driving for 2 days. I can only assume that the coach batteries are not charging when I am driving or they would be at peak voltage. I do have a factory solar charger on the roof and the red charging light is on.
So, please advise if you can help me.

Thanks for your time.

Looks for a solenoid in the battery control area.

With engine running, check volts on both large posts. At least one should be 13.4 or more volts. If both are not exactly the same, check volts on the small terminals.

If one small terminal has 12+ volts and the 2 big ones are not equal, the solenoid is most likely bad.

winnie32v · 10-23-2016, 02:52 PM

Quote:

Originally Posted by twinboat

Looks for a solenoid in the battery control area.

With engine running, check volts on both large posts. At least one should be 13.4 or more volts. If both are not exactly the same, check volts on the small terminals.

If one small terminal has 12+ volts and the 2 big ones are not equal, the solenoid is most likely bad.

Thanks,
Just went out and found the solenoid in the panel behind the second step.

Started the motorhome and here are my results:
(this solenoid has only 1 "small" terminal, two "big" ones.
Left Big Terminal = 14.34v
Right Big Terminal = 12.75v
Small Treminal = 13.92v

Engine Battery = 14.32v
Coach Batteries = 12.91v

My solenoid is: 97226-WR, 12v/cont
CAMDEC 00114 as descriptors.

Is this a NAPA or Auto Zone item?

So, I must assume that my solenoid is BAD?????
If you agree, please let me know AND where I might buy one. I am leaving for the south in a week and need to do this quickly.
Thanks for your help.

twinboat · 10-23-2016, 03:26 PM

Sound like you found it. The solenoid is getting activation power to the small terminal. The 14+ volts should pass thru it. They are a common failure item.

Just to be sure, since it grounds thru the base, are the mounting bolts tight and corrosion free.

You can pick up a solenoid at NAPA, but make sure it is a continuous duty type, capable of around 150 amps.

Most RV and boat suppliers should also have continuous duty solenoid.

If it has 2 small terminals, just use a short wire, from one of them, to a ground point, like one of the mounting bolts.

PULL the battery cables and unplug the shore cord, before diving in to the cables. Take pictures !!

l1v3fr33ord1 · 10-23-2016, 04:19 PM

Hold it- Don't replace that solenoid yet!

The test you should perform is to measure the "big terminal" voltages while someone inside presses the AUX START switch, both with the coach engine off and on. NOTE: the coach should also be unplugged from shore power and not on generator when performing these tests.

These are the tests "FIRE UP" recommended in post #6.

It's fully possible that the solenoid is fine, and a charging logic circuit is not. Or, a charging logic circuit may not exist, per my post #12.

okmunky · 10-23-2016, 04:28 PM

Quote:

Originally Posted by John Hilley

More than likely it is the battery isolation solenoid, a very common failure.

I had this same issue. When I went online to find a replacement the same exact solenoid was priced from $14.95 to $110.00.

I imagine some RV dealers sell them for even more. It pays to shop around!

CampDaven · 10-23-2016, 04:39 PM

I'm gonna replace the relay soon. For now, I press the battery boost switch a few times and it makes contact.

winnie32v · 10-23-2016, 04:43 PM

OK, Read post #'s 6, 12, 17.
1. I DO hear a "click" when I push the "Battery Boost" toggle on the dash. I will employ my wife in the AM and Unplug from shore, engine OFF, take readings across the 'Big' terminals with Battery Boost Toggle ON and Off to ensure that the solenoid IS functional.
I will do the same with engine ON.

Results will be posted.

Also, I just made one other check: With the shore plugged IN, The left Big terminal on the solenoid reads 12.70, the Right one reads 0, the Small one reads 0.

Does this help???

Is this enough to determine if the solenoid is bad and needs to be replaced?

Advise, please.