Sytem Shutdown outside Butte Mt

[Norm Green]

My wife and I are on a trip from Nashville to Seattle in our “06 Thunder, not the best time of the year for a trip across the northern states, but trying to get to Seattle to visit ailing relatives.  While driving across Montana yesterday, west bound on I90, I noticed that the Aladdin system indicated the battery charge was decreasing rather fast and I noted the volt meter indicated almost no charge.  A short while later, the “check engine” light came on followed by the “check tran” light.  Fortunately, we were approaching a truck pull-off area which I took.  Shortly after coming to a stop, putting the coach in neutral, the Aladdin system shut down, the transmission indicator went blank and the engine shut down.  I inspected the engine and saw nothing out of the ordinary.  Called for a tow and transported the coach back to Butte MT, about 15 miles back on I90.  The service shop, Baker Towing and Truck Repair, diagnosed the problem today as a bad alternator, replacement cost of about $1,500.  No unit in the area and the shop is having one shipped overnight and will replace it tomorrow.  We plan to get to Missoula once the coach is back running and then we will stay there until we have a good weather window to continue to Seattle.  I called Beaver Coach Sales Service and was told that the coach responded as expected with a severe low voltage condition.  I’m surprised that we lost the alternator and at the cost.  Fortunately we have an extended warranty which is covering most of the cost.  

[David T. Richelderfer]

So I have a question.  Do these high-end coaches have a safety system that shuts down the engine when the batteries get nearly discharged?  Would your coach's engine have shut down while traveling at cruising speed out on the freeway had you not pulled off?  Or is there a safety system that "senses" you stopped, your transmission is in neutral and the engine is idling, so it caused the shutdown?  Just wondering...

[Edie and Marty Hochberg]

Norm, and to anyone with a similar problem,

Next time this happens pull over as soon as is safe/possible.  Then start your generator.  As soon as it begins charging the chassis batteries you can continue your travels.  The Alladin, Cat ECM or Allison will be none the wiser and you will be able to get yourself to a repair facility.

You will need to use the "START BOOST" switch to get the generator started.

Hope this is helpful.

[Edward Buker]

I do not think a safety system was invoked here just for battery voltage, I think the voltage level was to a point where it would not sustain the ECMs or fuel solenoid, whatever item was the first to stop functioning electrically that was required to run these engines within spec. Given everything shut down the ignition solenoid may have released due to low voltage. It could  also have been an out of limit condition for one of the critical sensors due to low voltage, hard to guess what was the exact culprit.

Like Marty said, if the generator and house charger was active you could have continued. There are safety shut down limits for oil pressure, temperature, and other items but I do not think voltage would be an item they would invoke a shut down for.  A CAT dealer could tell you if they have a limit and a shut down value. Sometimes the safety systems will put you in limp mode and limit the speed you can travel at before shut down.

Later Ed

[Norm Green]

David, good question, I don't know which scenario is accurate.  I know as I slowed down  to stop, it appeared that things started to shut down.  I would hope that the engine/transmission would not shut down until the coach had come to a stop.

Marty, I had not thought about the generator.  I will remember this for the future, although I hope I never have to use it.  Being able to make it to Missoula would certainly been better regarding choices for repair facilities.

[Jerry Carr]

I had the alternator go out on our 06 Thunder a few years ago, we did use the APU to keep the batteries charged! we drove from Fresno to Bend to have the repair done.

[Roy Warren Co-Admin]

I had this happen to me, but I was told after I had the generator started to keep the "Battery Boost" switch on.  I did this by forcing something behind the spring laden switch and we were able to travel until we found a suitable repair station (2 days later).  I was told the generator will not keep the chassis batteries at a high enough charge and that the house batteries would maintain the charge with the generator.  If you keep losing voltage on the chassis, you might try this.
Roy

[Michael Marcocchio]

Hello Engine ECM plus Trans ECM takes about 9.6 volts min to operate after that low voltage they stop operating,hence they shut you down.So by starting your Gen it would provide you with at lest 13.5 volts to get you going again . Michael.

[Gerald Farris]

If you have a coach that is equipped with a "Bird" system, you only have to start the generator and have the inverter set to charge the batteries to maintain your batteries if the engine alternator fails. However if your coach has a conventional battery isolator, you will need to hold the boost switch down in order to recharge the chassis batteries with the generator.

Gerald

[Joel Ashley]

This may have been another case of letting the engine recharge batteries after dry-camping.  It's too big a load.  To avoid the cost of an alternator, always use the generator after dry-camping to recharge your battery banks before starting the engine to hit the road.

Joel

[David T. Richelderfer]

The "BIRD" system - Bi Directional Isolator Relay Delay.    http://www.dodgenmobiletech.com/sites/default/files/Intellitec%20Bi-Directional%20Isolator%20Relay%20Delay.pdf

Copied and pasted from the link:  The BIRD (BI-DIRECTIONAL ISOLATOR RELAY DELAY) performs two important functions.  It provides a method of charging the coach battery from the engine alternator and charges the chassis battery from the converter when the coach is plugged into shore power [or, I assume, when the generator is running].  When neither battery is being charged, the batteries are isolated from each other to prevent the loads of one battery from inadvertently discharging the other battery.  The unit is housed in a plastic enclosure suitable for mounting under the hood, out of direct water spray.  It operates in combination with a continuous duty solenoid to connect the two batteries at the proper times for charging.

The BIRD operates in conjunction with a continuous duty solenoid to provide the isolator/battery charging functions of a motor home. It senses voltage on the coach and chassis batteries. If the voltage on either one is above 13.1 volts, indicating the battery is being charged, it closes the isolator relay, paralleling the batteries, charging both. It operates in two directions, charging the batteries from the engine alternator and charging the batteries from the converter. These functions are similar but operate at different thresholds.

Okay... so I think I understand what the BIRD does, and even somewhat understand how the BIRD does it.  Now... how do I know if my coach has a BIRD?

[Joel Ashley]

Your link provided a diagram of the unit you are looking for, David.  Ours is mounted on the inside of the access door in the battery bay that covers the solenoid/isolator relay (between the coach and chassis disconnect switches as per your diagram) and the high amp coach fuses.  Yours probably is too.

Joel

[David T. Richelderfer]

I was rereading Norm's original post and I was wondering why Bend didn't tell him to start his generator to continue on to the next city of size.  Perhaps his coach batteries were also discharged - I don't know - so his generator would not start.  Also, if his coach batteries were otherwise okay, then he could have continued on for a limited mileage by pushing the boost button - yes?

[Joel Ashley]

The downside to holding the boost switch down, or overcoming its spring by sticking something under it like Roy did, is that it's designed as a momentary switch for engine start, hence the spring.  Forcing it to remain in the closed position can cause a solenoid to overheat and non-electronic components to burn and carbon up.  But if it resolves other pressing issues it is certainly an option, and in 28 years of motor homing I had to do it once myself.

Joel

[Joel Ashley]

Hey David, did you ever find your BIRD?

Uh, perhaps I should put that differently... Did you locate the bidirectional isolator relay delay?

Joel