House batteries charging

[bobbylinn52]

2007 Safari Cheetah SFD

C7 Cat, 350 HP

My house battery bank, four GC2 batteries,  doe NOT charge when traveling, engine alternator.  The house bank  charges fine on the generator and shore power.  The alternator is outputting 14+ volts keeping the chassis bank, two group 31 starting batteries charged fine.  I can tie the two banks together with the boost switch in the cockpit.  The Trombetta solenoid is working as expected.  I cannot find anything in the electrical or battery bays that looks like or is tagged as a battery isolator.  Would or should this coach have a battery isolator?  Can I install a Blue Sea 7622 ML-ACR, which I have, inlace of the Trombetta to allow the house bank to charge from the engine alternator?  Unfortunately I do not have the wiring diagrams for this coach.

 

Thanks, in advance.

Bobbylinn52

[jacwjames]

I had a BIRD, Isolation Solenoid, and a Lambert 415 which charged both battery banks if driving, on shore power, or running the generator.  But I started to have trouble with the Lambert so

I installed a Bluesea and got rid of all of the above.  I put the Bluesea in the same location as the isolation solenoid.  Easy install for that, took the wires off the solenoid, removed it, put the Bluesea in it's place and connected the house and chassis power cables.  But if you want to have the boost function at the dash to combine both batteries you may have to run an additional wire, I did.  That was the hardest part but once the wire was run the install of the switch was pretty simple.  The switch fit in the same hole, it is lighted and toggles for manual operation, off, automatic.  So if you want to isolate the two battery banks you can using the switch.

[1nolaguy]

Our 2005 Safari Cheetah has a similar electrical setup. All HB charging comes through the inverter charger. so it will charge the house batteries Batteries via shore power or the generator but not the alternator. Likewise the chassis batteries only charge through the alternator. You can add solenoids to charge the chassis batteries by the I/C or the house batteries by the alternator, but it can be involved and costly. I charge the chassis batteries when sitting using a 4 amp digital charger plugged into the I/C and via a 25w solar panel when in storage. The Throwbeta solenoid shown in your photos allows the the house batteries to supplement the chassis batteries if you are having trouble starting the engine do to low voltage in the chassis batteries. I had looked into allowing hose battery charging from the alternator but at the time the cost was not justified because of the way we travel. YMMV.  

[Donald]

Had same issue on are 2007 monaco knight. In ares in the front electric compartment. Small relay that know to fail it plugs into  the  circuit board. I watch  a U tube a  gentleman  was working  on a monaco  same issue .

[Ivylog]

Yes, you can wedge something under the boost switch to charge the house batteries.

[Tom Cherry]

1 hour ago, Ivylog said:

Yes, you can wedge something under the boost switch to charge the house batteries.

IVY....DOING THAT...>WEDGING A GOLF TEE > CAN BURN UP THE SOLENOID> This is NOT RECOMMENDED.....this has been posted many times.  Here is the LAST ONE.....

NOW…a DISCLAIMER, requires by our legal staff….LOL!

There are three brands or types of Battery Boost Solenoids.  They are mistakenly called “Big Biy”.  Sort of a tissue is called a Kleenex.  Some folks will put a golf tee under the boost switch and wedge it ON.  That ONLY works, BUT IS NOT A LONG RANGE RECOMMENDED PRACTICE, if you have the Trombetta or maybe a White Rogers boost.  They were made for CONTINUOUS full 12 VDC on the coil.  However, the real INTELLITEC Big Boy, in the 200 Amp rating (which is commonly used for MH) will burn up the coil.  It las a younger brother that is a 100 A version for just battery connections and NOT rated for the high current of using the Boost to try to aid the Chassis Batteries when low (that ain’t gonna work if the Chassis is dead….as even then, the contacts are NOT rated for full starting)

Ivy,,

In your case, you have a separate Intellitec Board that controls or uses the  Big Boy (200 Amp) for Bi-Directional Charging.  When your system (95% of the time is charging or maintaining) there is a reduced (or pulsed signal) that is sent to the 200 AMP Big Boy.  If you try to read it on a VOM, it will read in the range of maybe 4 Volts....as in my Camelot.  Yours will read a bit higher as it is a full 12 VDC, but pulsed rapidly to result in a lower voltage.  The Navigator due to the Intellitec board and it's pulsing is hard to "see".  On my Camelot, I have the Intellitec BIRD Diesel 2 Module. That is what keeps from burning up the Big Boy.  

BOTH your system (pulsed) and mine (reduced voltage) actually "Lock in or cycle" the Big Boy with a short shot of 12 VDC.  THEN, the voltage (or the equivalent pulsed voltage) is reduced.  The THEORY or the REALITY.  The Big BOY is NOT rated for continuous 12 VDC.  Read the Manual on how to use the BOOST for Charging and what to do.

If you wedge a golf tee under a 200 Amp Intellitec Big Boy....it will burn up the coil..100% guaranteed....THAT HAS HAPPENED.  THAT IS WHY THE GENERIC Statement about the Golf Tee is dangerous and can cause major damage.

NOW, if the Poster or whomever understand this...FINE....but most don't.  SO THE MODERATOR'S POSITION....

DO NOT DO THIS...IT IS AN UNSAFE PRACTICE.  Find and FIX the problem.

Hope this makes sense and you understand why we are so concerned about telling folks to potentially damage their electrical system with a practice that MIGHT have been OK for older MH....but you have to KNOW exactly WHICH Boost Solenoid you have and the ratings and the parameters before you can do it.

Thanks... 

[bobbylinn52]

Tom,  Does it matter if I remove the Trombetta and install the Blue Sea ML-ACR if I have a battery isolator somewhere that I have not found?  Evidently if I do have an isolator it is not working properly.  I have owned this unit since 2015 and the house batteries have never charged from the alternator.  In 2021 I converted my never cold to an 120V JC Refrigeration compressor unit so now I would like to have house charging from the alternator.

 

Thanks to all for the assistance in the replies above.

[Tom Cherry]

35 minutes ago, bobbylinn52 said:

Tom,  Does it matter if I remove the Trombetta and install the Blue Sea ML-ACR if I have a battery isolator somewhere that I have not found?  Evidently if I do have an isolator it is not working properly.  I have owned this unit since 2015 and the house batteries have never charged from the alternator.  In 2021 I converted my never cold to an 120V JC Refrigeration compressor unit so now I would like to have house charging from the alternator.

 

Thanks to all for the assistance in the replies above.

I am NOT the expert....but I have read a lot and I use the "SEARCH" function.  If you put in ACR in the search box and chose TOPICS....you get a covey of hits....and then if you pick everywhere, it really gets mind boggling.  I did that and here are some topics or threads to read.  There are a BUNCH of charging or no power or whatever topics going.  Looking back, they "COULD/SHOULD" maybe been merged as you get the same posts or info....and sometimes some very knowledgeable folks get tired and don't double post or respond to both....having said that....you need to FULLY understand that putting in the MC-ACR is not the ultimate answer.  I just posted a comment on that on the OTHER topic.  It requires making custom cables to adapt it.  It also requires running a new wiring harness to the front as the existing Monaco harness does not have enough conductors to make it work properly.  It also requires understanding what each component does and where they are located.

Van Williams is one of our GO TO GUYS.  We have MANY and each has their specialty....so this is NOT a put down of them. Van has tackled many of the electrical problems and his first "TOPIC" was well written and has many pages of Q&A and personal opinions.... So, I would START THERE...

OK....I DID a lot of research.  Here are the wiring Diagrams for your system.

file:///C:/Users/tomgc/Downloads/2006%20Monarch%20wire%20diagrams.pdf

NOW....if you scroll down to the bottom...and you MAY have these in your manual.  Look at the PRINT "Panel - 12 V Front Distribution"  It is print number 16616214.

You have a hybrid system....  there is an Intellitec Isolator Relay Delay.  It then is used to CONTROL a BOSCH relay.  Isolator Defeat Relay.

https://intellitec.com/wp-content/uploads/2022/02/53-00629-120-SERVICE-MANUAL-1.pdf

NOW....It is difficult for me to follow the wiring.  BUT, the Bosch Relay is supposed to allow the Intellitec to power or turn ON or provide a signal to the Trombetta.  You do NOT have the big finned Isolator Relay that is commonly posted here as you have a newer system and Monaco was fooling around with newer designs.  I would do TWO THINGS FIRST...

replace the Relay and see if that fixes the problem. Mine has such a relay in it and I have bypassed it or did at one time.  Put in a NEW or a known good relay.

Second....read the manual on how it works.  Then do some testing or trouble shooting and see if it is working.  

This has worked for many folks.....BUT, the prints are not exactly easy to follow....

OK....if you REALLY want to install the ML-ACR and have the $75 crimper for the large cable ends and the right size cable and fittings and also are prepared to run the new harness and then figure out HOW to make it work.....on the Boost Switch....then it is great.

https://www.monacoers.org/search/?q=acr&quick=1&type=forums_topic

I used ACR and got a lot of info.  You can try ML-ACR as well as limit it to TOPICS or also EVERYWHERE.  I personally would do a lot of research and try to resolve my existing problem.  BUT, if you really want BIRD or Bi-Directional Charging and are up to the task and DO understand what the rewiring of the switch is like...then by all means....GO FOR IT...

[Ivylog]

Tom, thanks for the heads up although I‘m well aware of the specifications of the BigBoy and how the voltage is pulsed.

I was replying to those who have a “Little Boy”… Trombetta 114-1211-020 which is a continuous duty solenoid.

Edited February 21, 2023 by Ivylog

[waterskier_1]

First, that relay (solenoid) is part of your Isolator Relay Delay (IRD) system.  I don't know the Safari hierarchy, but in the Monaco Line, the Diplomat and below had only an IRD meaning is was one-way.  It would allow charging the Chassis and House batteries from the main engine alternator, but it was not designed to allow charging of the Chassis battery from the Inverter/Charger running off shore or generator power.  The Dynasty and above had a BIRD (Bidirectional Isolator Relay Delay) which, as the name infers, allowed charging of both the Chassis and House batteries from either the engine alternator or the inverter/charger.  

Something is broken on your coach since ALL Monaco products charger both the Chassis and House batteries, by design.  You have narrowed it down to something in the IRD system board.  These are often in the Front Run Bay.  That is where the Battery Boost Switch is connected to the system also.  The purple wire is the control.  

Now, to answer the question about replacing the existing solenoid, yes you can do that.  Tom has provided a great reference on how to do this written up by Van Williams.  Your only concern will be enabling the Boost Switch function - for that, you will need to trace the purple wiring back to the switch, or run a new wire.  This is only to enable the Boost Function.  

  -Rick N.

Edited February 21, 2023 by waterskier_1
Forgot to include signature

[bobbylinn52]

Again, Thanks to all for the information above.  I have more homework to do but feel I better understand the systems I'm dealing with.  I will not install the Blue Sea ML-ACR till I better understand what is happening currently.

 

[Tom Cherry]

16 hours ago, waterskier_1 said:

First, that relay (solenoid) is part of your Isolator Relay Delay (IRD) system.  I don't know the Safari hierarchy, but in the Monaco Line, the Diplomat and below had only an IRD meaning is was one-way.  It would allow charging the Chassis and House batteries from the main engine alternator, but it was not designed to allow charging of the Chassis battery from the Inverter/Charger running off shore or generator power.  The Dynasty and above had a BIRD (Bidirectional Isolator Relay Delay) which, as the name infers, allowed charging of both the Chassis and House batteries from either the engine alternator or the inverter/charger.  

Something is broken on your coach since ALL Monaco products charger both the Chassis and House batteries, by design.  You have narrowed it down to something in the IRD system board.  These are often in the Front Run Bay.  That is where the Battery Boost Switch is connected to the system also.  The purple wire is the control.  

Now, to answer the question about replacing the existing solenoid, yes you can do that.  Tom has provided a great reference on how to do this written up by Van Williams.  Your only concern will be enabling the Boost Switch function - for that, you will need to trace the purple wiring back to the switch, or run a new wire.  This is only to enable the Boost Function.  

  -Rick N.

Rick,

The Intellitec Isolation Delay Relay is actually a small Electronic Module.  It then, if you look at the print, goes to a Bosch Relay.  That relay is what controls, I THINK, the boost switch.  So, in theory (reality???  this IS Monaco), the Intellitec delays the initial "HIT" of charging current, just like the big finned ones did.  The Bosch Relay, after the Intellitec has "Calmed down and the time or voltage is OK", is then energized and you have the Boost Solenoid (assumed to be full voltage rated coil) close....thus, as you drive, the house and chassis are charged.

That was the second evolution from the big old clunky finned Isolation Relay.....and then the NEXT step was to go to the Intellitec BIRD Module....and it then controlled a REAL Big Boy (200 A).....  The 200 A is PROBABLY what you have, but your's is contolled by a custom or speciality Intelltiec board...  On the lower food chain, the BIRD Module puts out a lower voltage to "Hold In" the coil without damaging it.

FWIW....  The Dynasty Big Boy will be LOUDER and BUZZ and be HOTTER than the same Big Boy used with the Intellitec BIRD Module.  Frank and I have exchanged info and tested and "felt".  Mine gets WARM and makes a little noise.  His (2008 Dynasty) is louder and hotter.  WE THINK that the pulsed signal (12 VDC?) from the Dynasty Intellitec board just puts out the equivalent of a "higher" holding voltage...maybe 8 or so and the BIRD Module is around 4 or so.

NOW you KNOW.....

[bobbylinn52]

Well, I have done some more digging in the Cheetah.  Below are pictures of two relays in the front left hand electrical bay under the driver.  I am thinking one or both of these could be my issue with alternator charging house batteries.  Can anyone tell me if these would be plugged into or soldered into their boards?  I gently tried to pull on them and they did not move any.  Also how would I test these?  I am MUCH better with mechanical systems than electrical.

[Tom Cherry]

1 hour ago, bobbylinn52 said:

Well, I have done some more digging in the Cheetah.  Below are pictures of two relays in the front left hand electrical bay under the driver.  I am thinking one or both of these could be my issue with alternator charging house batteries.  Can anyone tell me if these would be plugged into or soldered into their boards?  I gently tried to pull on them and they did not move any.  Also how would I test these?  I am MUCH better with mechanical systems than electrical.

Best I can tell….Monaco cheated.  You don’t have the Intellitec that was called out on the prints.  Look at the print.  The lower back one is the Bosch style relay.  Assume it is a plug in.  Order a new one, Amazon has the REAL Bosch 87/87A 5 pin relay.  Put it in.  Then try it.  When you have someone hold on the boost switch, you need to have a VOM.  Measure across the large studs.  There should NOT be more than 0.05 or so volts.  Then let off on the boost switch.  NO VOLTS.

that means the Bosch relay is working.  OK.  Next up.  Read the manual I gave you.  The isolator relay is probably just screwed down or fastened to the board and does not have an electrical connection.  The 3 wires are the same that come out of the Intellitec.  If it doesn’t work (there is a test and trouble shooting guide). It is dead.  You might find one if you Google.  But if not, the the Intellitec will work….but you need to determine which leads go where.  You will use the 3 pin connector, but I can’t tell you which wires to splice or connect together.  Google your unit and find a print or manual…then read it.  Then you will know which wires to connect.

Aif that is not your forte, find an electrical savvy MH buddy or get a tech to fix it.  

[waterskier_1]

1 hour ago, bobbylinn52 said:

Well, I have done some more digging in the Cheetah.  Below are pictures of two relays in the front left hand electrical bay under the driver.  I am thinking one or both of these could be my issue with alternator charging house batteries.  Can anyone tell me if these would be plugged into or soldered into their boards?  I gently tried to pull on them and they did not move any.  Also how would I test these?  I am MUCH better with mechanical systems than electrical.

The top picture shows the Isolator Relay Delay (IRD) board.  It may not be made by Intellitec, but it serves the same function.  The Blue Wire should be +12VDC supplied from a switched Ignition source (only has power when the ignition is turned ON).  The Black Wire should go to a GROUND.  The Red Wire is the control output wire.  It should provide +12VDC when the IRD board is satisfied that the ignition is turned on and the voltage is greater than about 13.3VDC (when the alternator is running it will be about 14.2VDC) for about 12 Seconds - time for the engine to maintain an idle and sense the voltage.  That Red wire then controls the Black Relay on the lower PWB.  This is likely a standard automotive relay - what Tom calls a Bosch (a specific brand).  From the looks in the picture, it is soldered onto the board - I can't see a plug-in socket.  

To test this, you will need a voltmeter.  Try and see if you can insert a sewing straight pin in the 3-connector plug.  Confirm that you have 12VDC or greater between the Blue and Black wires when the ignition switch is turned on.  Then start the engine and confirm the voltage increases above 13.3 volts (still between the Blue and Black wires).  If so, then the IRD is getting correct voltages to operate.  Next move one test lead and straight pin from the Blue Wire to the Red Wire.  If the engine has been running for more than 12 Seconds, you should have 12VDC or greater between the Red Wire and the Black Wire.  If that passes, then the small IRD circuit board is working.  The next test is not as straight forward, since I don't have the exact wiring diagram for your coach.  But, Monaco typically used Violet (Purple) or a Violet striped wire to go back to the large Trombetta Relay (solenoid) shown in the pictures of your original post.  You should have 12VDC on the violet wire connected to that relay.  If you do, the relay should be energized, and you should have the same voltage from both the large terminals to ground.  If there is more than 0.5 Volts difference, the contacts are dirty.  

Hope this helps.  If you have questions, post and I'll try to help.

  -Rick N.

[Tom Cherry]

1 hour ago, waterskier_1 said:

The top picture shows the Isolator Relay Delay (IRD) board.  It may not be made by Intellitec, but it serves the same function.  The Blue Wire should be +12VDC supplied from a switched Ignition source (only has power when the ignition is turned ON).  The Black Wire should go to a GROUND.  The Red Wire is the control output wire.  It should provide +12VDC when the IRD board is satisfied that the ignition is turned on and the voltage is greater than about 13.3VDC (when the alternator is running it will be about 14.2VDC) for about 12 Seconds - time for the engine to maintain an idle and sense the voltage.  That Red wire then controls the Black Relay on the lower PWB.  This is likely a standard automotive relay - what Tom calls a Bosch (a specific brand).  From the looks in the picture, it is soldered onto the board - I can't see a plug-in socket.  

To test this, you will need a voltmeter.  Try and see if you can insert a sewing straight pin in the 3-connector plug.  Confirm that you have 12VDC or greater between the Blue and Black wires when the ignition switch is turned on.  Then start the engine and confirm the voltage increases above 13.3 volts (still between the Blue and Black wires).  If so, then the IRD is getting correct voltages to operate.  Next move one test lead and straight pin from the Blue Wire to the Red Wire.  If the engine has been running for more than 12 Seconds, you should have 12VDC or greater between the Red Wire and the Black Wire.  If that passes, then the small IRD circuit board is working.  The next test is not as straight forward, since I don't have the exact wiring diagram for your coach.  But, Monaco typically used Violet (Purple) or a Violet striped wire to go back to the large Trombetta Relay (solenoid) shown in the pictures of your original post.  You should have 12VDC on the violet wire connected to that relay.  If you do, the relay should be energized, and you should have the same voltage from both the large terminals to ground.  If there is more than 0.5 Volts difference, the contacts are dirty.  

Hope this helps.  If you have questions, post and I'll try to help.

  -Rick N.

You, 

My learned friend have solved the mystery.  Which wire goes where.  As long as the Bosch is working….and that is what energizes the battery boost solenoid for withe supplemental starting as well as charging house while driving, then the next step is verify the function of the IRD.  IF that model is still working, replace.  If not put in the Intellitec IRD.  

THANKS

[bobbylinn52]

Rick N.  

I have checked the voltages as you suggested above.

The black wire is ground

The blue wire is a switched +13.7 VDC with the ignition on engine not running, 0 VDC with the ignition off

The red wire has +13.7 VDC with the engine running

There are a couple of purple wires from the board labeled "Isolated Defeat Relay" and a couple of Red wires.  Neither of the purple wires have voltage on them, engine off or running.  I did not meter the red wires, shame on me.

In the photo below you may note a purple wire disconnected and taped.  This is the wire that originally triggered the salesman switch relay that I deleted.

The Trombetta solenoid in the battery bay does not have control voltage unless the battery jump switch is activated, engine running or not.  I believe this solenoid is rated for continuous duty.

I am prepping for a 3 week trip departing next week.  What is your opinion of the golf tee under the boost switch or installing the Blue Sea ML-ACR  7622 without the remote switch wired in.  I would leave the ML-ACR in the auto mode.  I would do this till I return from our trip and can run the wires for the remote switch in the cockpit.

 

 

 

[waterskier_1]

44 minutes ago, bobbylinn52 said:

Rick N.  

I have checked the voltages as you suggested above.

The black wire is ground

The blue wire is a switched +13.7 VDC with the ignition on engine not running, 0 VDC with the ignition off

The red wire has +13.7 VDC with the engine running

There are a couple of purple wires from the board labeled "Isolated Defeat Relay" and a couple of Red wires.  Neither of the purple wires have voltage on them, engine off or running.  I did not meter the red wires, shame on me.

In the photo below you may note a purple wire disconnected and taped.  This is the wire that originally triggered the salesman switch relay that I deleted.

The Trombetta solenoid in the battery bay does not have control voltage unless the battery jump switch is activated, engine running or not.  I believe this solenoid is rated for continuous duty.

I am prepping for a 3 week trip departing next week.  What is your opinion of the golf tee under the boost switch or installing the Blue Sea ML-ACR  7622 without the remote switch wired in.  I would leave the ML-ACR in the auto mode.  I would do this till I return from our trip and can run the wires for the remote switch in the cockpit.

 

 

 

Linn,

Are you sure the purple wires say "Isolator DEFEAT Relay" or might they have said "Isolator DELAY Relay"?  In any case, something on the big board may be defective.  Unless you have advanced electronic troubleshooting skill and equipment, I would wave the white flag.

Your next question is a no-brainer for me.  Install the Blue Seas Automatic Charging Relay (ACR).  The thought of driving with a golf tee, popsicle stick, or anything under the BOOST switch is ludicrous.  That would result in both battery banks always being connected together - both for charging and discharging (for as long as the object stayed wedged).  If that is the result you are looking for, the better way to accomplish this is to connect the two large cables on the "Trombetta" Relay.  Just remove one from one terminal and put it on the other terminal.  But recognize that your coach will be drawing power (current) from both batteries.  The size and condition of the batteries will determine how much from each.  

Hands down, the Blue Seas ML-ACR is the best choice, and will result in a system that is as good, or better (depending on whether you have an IRD or BIRD) since it will be bidirectional.  It will also draw much less current and generate much less heat.  

  -Rick N.

 

[bobbylinn52]

Rick,

The relay on the bottom board in the images I posted definitely says “Isolate Defeat Relay”. I will install the ML-ACR. 
 

Thanks for all the guidance and help. 

[Tom Cherry]

12 hours ago, bobbylinn52 said:

Rick N.  

I have checked the voltages as you suggested above.

The black wire is ground

The blue wire is a switched +13.7 VDC with the ignition on engine not running, 0 VDC with the ignition off

The red wire has +13.7 VDC with the engine running

There are a couple of purple wires from the board labeled "Isolated Defeat Relay" and a couple of Red wires.  Neither of the purple wires have voltage on them, engine off or running.  I did not meter the red wires, shame on me.

In the photo below you may note a purple wire disconnected and taped.  This is the wire that originally triggered the salesman switch relay that I deleted.

The Trombetta solenoid in the battery bay does not have control voltage unless the battery jump switch is activated, engine running or not.  I believe this solenoid is rated for continuous duty.

I am prepping for a 3 week trip departing next week.  What is your opinion of the golf tee under the boost switch or installing the Blue Sea ML-ACR  7622 without the remote switch wired in.  I would leave the ML-ACR in the auto mode.  I would do this till I return from our trip and can run the wires for the remote switch in the cockpit.

 

 

 

Not Rick, but my take.

First.  If I understand.  The Trombetta works or you have measured voltage on the coil.  Next would be to test the Trombetta to make sure the contacts are OK.  
 

You need, with the engine RUNNING and no shore power, to measure, from Ground, the voltage on either side of the Trombetta studs.  One side will be Chassis and the other side ground.  You will see two totally different voltages as the Chassis will be higher.

Then hold on the boost.  Remeasure.  Should be the same as the Chassis battery as it is the higher potential.  

Next…..measure the voltage from Stud to Stud.  That should be less than 0.05 - 0.10 VDC.  That means the contacts are in good shape.

Next, write down the Part Number of the Trombetta.  Look it us.  You should easily find the specs and then verify that it is rated for continuous voltage.

IF a all the above is correct, then you DO have a functional Boost system and the “device” that is supposed to trigger the Bosch solenoid is the problem.

As far as your trip goes, you have two options.  I would use a Jumper Cable from the Positive on the House to the Chassis if I wanted to charge the  House.

NOW…comes the decision, replace your defective device with the Intellitec.  There are TWO wires on one side of the Bosch relay coil (look at the print).  Measure the voltage on the coil leads and then push in the boost.  Which ever lead supplies power…..that is where you put the OUTPUT lead from the new Intellitec.  It is as simple as that.

As long as your Trombetta is OK as in good contacts, then the cheapest way is to fix the original design with the Intellitec and then have road charging.  

The MLACR was designed so that you had bi-directional charging so when you were camped, the Chassis batteries were being charged.  It was also designed so that when in storage, your Chassis battery was being charged.  If you don’t have power for when the MH is sitting, then there is very little, if any, advantage, from the ML-ACR.  Most people that installed it either had a bad IRD or a bad Trombetta or wanted to have storage charging to keep the Chassis charged.

If that makes sense to you…then you make the call.  Now, some got tired of the complicated (perhaps mystique) of the whole system and decided to simplify and install the ML-ACR.  Just understand the above and then decide what to do.

Good Luck
 

 

by having someone hold on the Battery Boost Switch?  If that works, then you know the Bosch Relay is working.  Unfortunately, Monaco like relays and used them when a normal circuit would work.  SO…if your

[Steven P]

I've had this issue before.  When I bought my coach my alternator didn't charge the house batteries either. I found the isolator relay delay had failed for one so I replaced it.  Still didn't work.  I don't know the source of the blue wire voltage by mine never went above 12.2V.  I figured dirty contacts.  The chassis voltage stud read equal or greater than 13.2V when the engine is running so i tied into that stud and that works fine.  Later I had to replace the trombetta (and used the one w silver contacts)  all working well. 

[Tom Cherry]

4 hours ago, Steven P said:

I've had this issue before.  When I bought my coach my alternator didn't charge the house batteries either. I found the isolator relay delay had failed for one so I replaced it.  Still didn't work.  I don't know the source of the blue wire voltage by mine never went above 12.2V.  I figured dirty contacts.  The chassis voltage stud read equal or greater than 13.2V when the engine is running so i tied into that stud and that works fine.  Later I had to replace the trombetta (and used the one w silver contacts)  all working well. 

Steven,

great input and help.  You also pointed out that even the Trombetta, since if is “charging” constantly as it does not have the BIRD circuitry in the later versions…..which only closes if either House or Chassis needs them…..

Many folks have had the failed Trombetta and when they replaced, they went to the higher grade (Monaco uses the standard cheaper one)…as they last longer.

More info for the OP so he can make an intelligent decision on what his best option is, coastwise, for his anticipated needs and use.

Thanks…

[waterskier_1]

16 hours ago, bobbylinn52 said:

Rick,

The relay on the bottom board in the images I posted definitely says “Isolate Defeat Relay”. I will install the ML-ACR. 
 

Thanks for all the guidance and help. 

I wish I had a wiring diagram for your coach (or for the Monaco equivalent ).  I remember that Monaco added circuitry to disable "something" so that the ALT FAIL light didn't come on when both the alternator and generator (or shore power) were present at the same time.  This occurred due to the type of alternator sensing they incorporated.  I'm now wondering if what you have is the cure Monaco incorporated.  If so, the likely functionality is that it would sense the generator running and at the same time sense the alternator is running, and then disconnect or disable the charging circuitry.  That would solve the ALT FAIL false indication, since the House and Chassis systems would be separated when both the generator and the alternator were both operating.  If I had a wiring diagram, I could sort it out.  If anyone has a wiring diagram showing the incorporation of the Isolator Defeat or ALT FAIL cure, please post it to the files.

  -Rick N.

[bobbylinn52]

Thanks again for all of the GREAT research, information and trouble shooting help.  I am going to install the ML-ACR that I have and not try to repair the sensing circuits installed by Monaco.  I have tested the trip wires feeding the Trombetta and it does not have power unless the boost switch is held down.  There are actually two wires on the trip terminal, purple and white.  I have not taken these wires off and tested individually but when on the terminal there is no power unless the boost switch is depressed.  The white wire on the second small terminal appears to be a ground wire.  My next step will be to get a long test wire and trace down the purple and white wires.  I hope they both go to the front of the rig so I can use them for the ML-ACR remote switch.

 

Again  THANKS TO ALL!

[Tom Cherry]

37 minutes ago, bobbylinn52 said:

Thanks again for all of the GREAT research, information and trouble shooting help.  I am going to install the ML-ACR that I have and not try to repair the sensing circuits installed by Monaco.  I have tested the trip wires feeding the Trombetta and it does not have power unless the boost switch is held down.  There are actually two wires on the trip terminal, purple and white.  I have not taken these wires off and tested individually but when on the terminal there is no power unless the boost switch is depressed.  The white wire on the second small terminal appears to be a ground wire.  My next step will be to get a long test wire and trace down the purple and white wires.  I hope they both go to the front of the rig so I can use them for the ML-ACR remote switch.

 

Again  THANKS TO ALL!

The only thing I might suggest.  Look at your files.  I could not find ind a wiring schematic for the actual switch.  The switch appears to be a single pole, single throw so there is only 2 wires for the switched terminal.  TYPICALLY, MONACO used the House DC for the boost circuit.  Later on, the Dynasty had dual power, I think, so the boost woul work from either House or Chassis.  There should be 4 wires on the switch.  1 is incoming 12 VDC from house; 1 is outgoing to the relay; 1 is ground so the “NIGHT LIGHT” is lighted from the dash lights; The final one will be the 12 VDC from the dash light circuit.  If there is a red or pilot indicator when the  switch is engaged, it probably has a jumper from the wire to the Bosch relay.

That Bosch relay is now redundant and can be pulled.  Follow the install instructions and hardwire per the prints.

I keep forgetting that your Trombetta may be up front.  So the wiring run is shorter and easier. Later on Monaco moved the boost solenoid to the rear to keep the voltage higher so the new multi conductor wiring you need is a PITA to pull and run.