House batteries not charging

[jacwjames]

Originally Posted by vito.a

Maybe this is a good application for a Blue Sea Automatic Charging Relay. Everyone that has installed one says they are the best. It comes with a lifetime guarantee.
https://www.amazon.com/Blue-Sea-Syst...a-434132500260

I was having trouble with my system, different the yours but still a pain in the but. My Lambert did not seem to be keeping the chassis battery charged. So I decided to just replace the Lambert, BIRD, and Isolation Relay with the Bluesea.

So far so good, took a ~4700 mile trip and it worked flawlessly.

[windsorbill]

Originally Posted by YC1

I know Bill.

The power come up in parallel wires. Heavy duty ones. The harness for the coach is made up of three basic parts.

The long stretch from front to back is generic and the ends are added to build the model under construction.

Those heavy duty wires come into a small fuse box below the large box up front. One path is from the engine batteries and the other from the house batteries.

There are "chassis splices" in two places on mine. These splices connect the heavy cables together. In some cases these splices have given all kinds of strange and difficult symptoms to sort out.

See if you have a smaller fuse block below the large one. If so, you will notice some heavy wires coming in there.

To add to the dilemma the House/Salesman relay/solenoid gets involved and the long runs of wire can cause large voltage drops along the way.

Then of course are the miriad of grounds hidden in some places.

Taking a shotgun approach at any problem can just lead to additional unintended problems all too often.

Getting reliable information from voltage readings is paramount. Even if this takes some weeks or months of scratching your head.

Know your systems better now I feel it should be quite easy to diagnose your problem or problems. Often there is more than one problem and completely unrelated.

It seems I never have just one problem at a time. I am thankful every time being a well seasoned electronic tech with 50 years or more diagnosing things.

Thanks Myron. Every little clue seems to help. I don’t have those smaller fuse boxes but I do have a post in generator compartment with 3 heavy gauge wires. 2 come from the back, but haven’t traced them yet. The other goes into the large fuse box in front bay.

I feel confident we are getting accurate voltage readings. I’m using a fluke true rms. I’m consistently getting noticeably lower voltage on circuit board than engine batteries. I’ve tested countless times with engine on,off, shore power on,off.

[windsorbill]

Originally Posted by jacwjames

I was having trouble with my system, different the yours but still a pain in the but. My Lambert did not seem to be keeping the chassis battery charged. So I decided to just replace the Lambert, BIRD, and Isolation Relay with the Bluesea.

So far so good, took a ~4700 mile trip and it worked flawlessly.

Thanks Jim. That is definitely an option. Even if I go that way, I’d like to figure out why I’m getting low voltage on my panel.

[YC1]

Originally Posted by windsorbill

Thanks Myron. Every little clue seems to help. I don’t have those smaller fuse boxes but I do have a post in generator compartment with 3 heavy gauge wires. 2 come from the back, but haven’t traced them yet. The other goes into the large fuse box in front bay.

I feel confident we are getting accurate voltage readings. I’m using a fluke true rms. I’m consistently getting noticeably lower voltage on circuit board than engine batteries. I’ve tested countless times with engine on,off, shore power on,off.

Absolutely normal but without posting the exact numbers I can only guess if yours are normal.

The long runs of wire and varying loads will reduce the voltage when downstream. Keep in mind the cautions with extension cords. Using the correct gauge cords and keeping the lengths as short as possible. Same applies with the coach. It is a very long run up to the front. You have to also take into account that the negative side of the current run is inline with the positive feed. That is, power flows from the battery, through the loads, and back to the battery. People often forget the Ground side of the systems and voltage/current can get reduced on that side as well.

If you want to break your system down and troubleshoot by substitution just start at the IRD. Unplug the molex connector (inspect the pins), and using a 12 volt test light connected to one of the big battery/voltage posts inside the compartment insert the probe into the pin that is the output of the IRD.

The resistance of the test light will protect much like a fuse and give you an indication of a complete circuit. That is, the path back to the Trombetta.

The Trombetta may not pull in with this reduced voltage but you can take a voltage reading at the solenoid and make note that it comes and goes (even though half of the source voltage), so you are comfortable that the path is working.

With confidence that the path is working, use the same voltage source and build a test cable with an inline fuse holder. Then apply the voltage to the same pin. Measure the voltage at the relay again. The relay should be engaged and the voltage close to that source you are using.

Be sure to measure both small terminals on the relay. We don't want to miss a potential bad ground by not taking that critical measurement.

Now that you can toggle the solenoid in the back be sure to check the large terminals each time you are testing as well. Things could always lead back to a defective solenoid even though it has been changed.

My solenoid was bad at the two year mark. It was full of green goo crap that I was just stunned to see when opening it. I have opened a hundred solenoids over the years and this one was an absolute mess. I surmised the heating and cooling of the thing that will burn your fingers worked to draw in moist air when cooling and the way it was mounted did not allow for the escape of the moisture when it re-heated.

Yes, relays often have a right side up but I don't think I have ever seen one with that caution written on them. They can and do fill with water. Can't tell you how many over the years I changed because they were upside down and full of water while mounted under the hood of a car.

[windsorbill]

Originally Posted by YC1

Absolutely normal but without posting the exact numbers I can only guess if yours are normal.

The long runs of wire and varying loads will reduce the voltage when downstream. Keep in mind the cautions with extension cords. Using the correct gauge cords and keeping the lengths as short as possible. Same applies with the coach. It is a very long run up to the front. You have to also take into account that the negative side of the current run is inline with the positive feed. That is, power flows from the battery, through the loads, and back to the battery. People often forget the Ground side of the systems and voltage/current can get reduced on that side as well.

If you want to break your system down and troubleshoot by substitution just start at the IRD. Unplug the molex connector (inspect the pins), and using a 12 volt test light connected to one of the big battery/voltage posts inside the compartment insert the probe into the pin that is the output of the IRD.

The resistance of the test light will protect much like a fuse and give you an indication of a complete circuit. That is, the path back to the Trombetta.

The Trombetta may not pull in with this reduced voltage but you can take a voltage reading at the solenoid and make note that it comes and goes (even though half of the source voltage), so you are comfortable that the path is working.

With confidence that the path is working, use the same voltage source and build a test cable with an inline fuse holder. Then apply the voltage to the same pin. Measure the voltage at the relay again. The relay should be engaged and the voltage close to that source you are using.

Be sure to measure both small terminals on the relay. We don't want to miss a potential bad ground by not taking that critical measurement.

Now that you can toggle the solenoid in the back be sure to check the large terminals each time you are testing as well. Things could always lead back to a defective solenoid even though it has been changed.

My solenoid was bad at the two year mark. It was full of green goo crap that I was just stunned to see when opening it. I have opened a hundred solenoids over the years and this one was an absolute mess. I surmised the heating and cooling of the thing that will burn your fingers worked to draw in moist air when cooling and the way it was mounted did not allow for the escape of the moisture when it re-heated.

Yes, relays often have a right side up but I don't think I have ever seen one with that caution written on them. They can and do fill with water. Can't tell you how many over the years I changed because they were upside down and full of water while mounted under the hood of a car.

Some great suggestions Myron. Thanks. . I have done the test leading from the ird to the trombetta with an alternate source and it does engage. I can hear it but also voltage test confirmed it’s closing. I can also press battery boost rocker switch under steering wheel while driving, and can see instant voltage increase on my victron app.

I’m loosing anywhere from .7-1.0 volt from chassis batteries to the circuit board where ird is mounted. So circuit board is below the ird close voltage requirements (13.2 for 12 seconds). Alternator is putting out about 13.7.

Maybe I should have alt looked at.

I’ve started to look at all connections including grounds. Monaco got real creative hiding those.

Thanks for the ideas.

[YC1]

What voltage do you get at the IRD at high idle?

If you get enough at high idle then it will charge going down the road but of course you have indicated it does not.

That said, going back to a previous poster and without reading all through again, what is your voltage on the batteries at idle??

The voltage drop from the chassis batteries to the IRD may be absolutely normal but the voltage at the batteries could be too low.

If you want to experiment try this. Connect to shoreline and check the voltage on the house batteries. Should be fairly high. Then go find that or near that voltage in the front run bay where the IRD lives.

Cut the ignition sense wire on the ird and run the power from the higher voltage and the IRD should fire off.

Of course you already know it seems to work at times so is living on the edge. Many components change over life and the IRD could be a bit sensitive in its old age.

If you are seeing a weak voltage on the chassis batteries at idle your alternator could indeed be a bit weak. They have multiple diodes and one can fail. It is a bit tricky to diagnose for the weekender but usually a simple voltage test across the batteries tells the story.

Many have already suggested some improvements in your system and since you are very comfortable with the paths that the wiring take and how your system is supposed to work it would be a great time to go ahead and make the change.

Remove or unplug the IRD. Heck, take it out and put it on a work bench with a power source. Easy to bread board it for fun.

The Blue Seas device has a great following here. It might be a bit of overkill since your emergency start button system functions great.

You can go with the intellitec device that has the generator sense line if you want to keep things mostly stock. Mount right outside the big box and it will become a BIRD versus your IRD.

As for chasing less than one volt drop from your batteries to the IRD. I think you will be chasing a ghost. It does not hurt to chase those wires and exercise each connection along the way and clean and tighten every ground but probably won't solve your issue.

It will give you a very close relationship with your mansion on wheels and probably a few fresh places to install band aids.

I like to inspect and chase hidden ground and wires after dark because the bright light does not wash out or shadow things as much.

When someone has a problem I wish I had a good schematic/drawing application so we could work out the problem and then save the information by yr and model. Much of that I have for a few year range of mine but it sure would be nice to have schematics with specific notes. Such as voltage readings at various places.

Motorola used to have the best schematics in the world on their products. Voltage readings and notes everwhere. Even then I would copy schematics and make my own notes and readings. It made chasing the same ghosts much easier the next time.

[windsorbill]

Myron

Thanks for taking the time to respond. Ive already done most of those tests. Voltage doesn’t vary at idle, high idle. Just low voltage from where the ird reads it

After we get back from this trip in a couple weeks, I’ll probably go the blue sea route. Ive spent hours trying to find current problem without much luck.

For those that installed the blue sea already, you swapped out for the trombetta, where did you run the sensor wires?

Also did you just replace the OEM boost switch by the steering wheel with the one supplied with the ACR.?

[RCLImperial]

I recently found this thread and the original symptoms are remarkedly similar to whit I found in my 04 Imperial. The house battery charging was hit or miss when traveling, and hitting the boost switch would correct the problem. What I discovered was that the stitched ignition lead to the IRV was always less than the battery voltage. I suspected that the pc board trace was loaded with multiple items and the resistive drop was enough to keep the IRV from switching on the “Big Boy” , actually a White-Rodgers in my case. My solution was to find a solid battery voltage point on the board and use a relay to connect the IRD to that point. Since the IRD calls for switched ignition point, I used the original point for the blue lead on the pc board to drive the coil of the relay. That solution has worked flawlessly for the last ten years and was cheap.

Dick L. 04 HR Imperial

[YC1]

Originally Posted by RCLImperial

I recently found this thread and the original symptoms are remarkedly similar to whit I found in my 04 Imperial. The house battery charging was hit or miss when traveling, and hitting the boost switch would correct the problem. What I discovered was that the stitched ignition lead to the IRV was always less than the battery voltage. I suspected that the pc board trace was loaded with multiple items and the resistive drop was enough to keep the IRV from switching on the “Big Boy” , actually a White-Rodgers in my case. My solution was to find a solid battery voltage point on the board and use a relay to connect the IRD to that point. Since the IRD calls for switched ignition point, I used the original point for the blue lead on the pc board to drive the coil of the relay. That solution has worked flawlessly for the last ten years and was cheap.

Dick L. 04 HR Imperial

Great idea. Grabbing a good voltage source nearby and passing it through a relay that will close at less than twelve volts.

Bypasses any aging connections for sure. A bosh relay should work just fine. Lots of them used on the RV and about $5 at an automotive store.

[windsorbill]

Originally Posted by RCLImperial

I recently found this thread and the original symptoms are remarkedly similar to whit I found in my 04 Imperial. The house battery charging was hit or miss when traveling, and hitting the boost switch would correct the problem. What I discovered was that the stitched ignition lead to the IRV was always less than the battery voltage. I suspected that the pc board trace was loaded with multiple items and the resistive drop was enough to keep the IRV from switching on the “Big Boy” , actually a White-Rodgers in my case. My solution was to find a solid battery voltage point on the board and use a relay to connect the IRD to that point. Since the IRD calls for switched ignition point, I used the original point for the blue lead on the pc board to drive the coil of the relay. That solution has worked flawlessly for the last ten years and was cheap.

Dick L. 04 HR Imperial

Dick

Thanks for posting. I did find low voltage through the ignition when I took the ignition switch apart last week.

I think you’re on to something. Maybe I can get this resolved.

[windsorbill]

Originally Posted by windsorbill

Dick

Thanks for posting. I did find low voltage through the ignition when I took the ignition switch apart last week.

I think you’re on to something. Maybe I can get this resolved.

Just to conclude this thread in case any one has the same issue.

I've had a low voltage problem in the front run bay for who knows how long. I never realized it since most of the time we have the generator running, which in turn, charges the house batteries.

When running down the road, without the genny on, we had 13 or lower volts in the front run bay, which would NOT trigger the IRD to connect the BB relay. Getting to our destination, our house batteries were down and needed a charge.

I know this coach pretty well, but the low voltage had me scratching my head. But with everyones comments, and Dick L's similar issue, I did the relay Dick L had done. Should have thought of that early on, but sometimes you just need the obvious nudge.

Either way, got it fixed. Still have the low voltage in the front run bay, but that doesn't seem to effect anything, at least so far. And the house batteries are now charging like they should.