Charging System Issue

[ScottyB410]

I replaced both the BIRD and Trombetta. I think you will find that most of the new coaches are coming equipped with the BIM

[bigben]

ScottyB410 - very interested in the BIM as it will eliminate a failure point. At almost $200, I'd like to make sure I understand the replacement wiring. The Ing Org wire on the BIRD would go to the ING on the BIM. The PWR GRD black would go to the Gnd side of the BIM. Where will the Coach Bat Red go on the BIM? Where will the Isol Rly Coil Wht on the BIRD connect. I understand the large connections on the BIM replacing the solenoid large connectors. What is connecting to the Sig on the BIM. I've attached pictures of both the BIM and BIRD/Relay Solenoid.

Thanks

[Oneilkeys]

Here’s a description and wiring diagram for the BIM225.

[bigben]

Thanks for the diagrams - they help. Still am not sure on GEN SET or DASH SWITCH as the BIRD has neither of these. Any ideas?

[ScottyB410]

Just hopping on a plane. Ill answer tomorrow.

The diagram above is not the BIM. You only need three wires as there is no output to trigger a solenoid as it is all internal to the BIM. It is a BIRD and a Solenoid in one.

[Oneilkeys]

Looking at it again, it seems that the BIM160 might be the best replacement for the BIRD. It us rated for 160 continuous amps and the BIRD literature says it protects up to 150 positive amps.
The BIM does not have a generator connection so it makes it more straight forward. The relay core wire from the BIRD is not used - as ScottyB410 indicates that is internal in the BIM because it is a BIRD and Trombetta combined. The ignition wire goes to the ignition connection in the BIM and the Coach Battery to the Sig connection for the emergency start. I do not know if there is a fuse in that line to the emergency start, so I would put a 5 amp in that wire before I hooked it up to the BIM. In the Axis i am still not sure exactly how the emergency switch is set up, so I am interested to see what ScottyB410 has to say on this issue.
Good luck. I might buy one of these things just to have in my spare parts box.

[Oneilkeys]

As you can see from this diagram, the BIRD senses the coach battery charge thru the coach battery wire that goes to the battery isolator which is hooked to the coach battery post of the Trombetta. The emergency start switch cuts off of that wire to the relay coil wire hooked to the Trombetta post that opens and closes the Trombetta. Except for the emergency start switch, that is not necessary with the BIM because it is internal in the BIM.
The wire coming from the other side if the emergency start switch has to be connected to the “Sig” terminal on the BIM. That wire should be the wire connected to the positive terminal of the Trombetta. If you cut and seal the relay coil wire coming off the BIRD and hook up the wire from the positive post of the Trombetta you should have a connection directly from the coach battery to the Sig terminal. The final thing would be to remove that wire from the coach battery wire from the BIRD that goes to the coach disconnect. This is no longer needed because it is internal in the BIM.
I am assuming that your wiring is similar to mine and that mine closely follows the “normal” BIRD wiring. You know “assume” - make an “ass” out of “u” and “me”. Especially appropo with Thor.

[ScottyB410]

Sorry, late to the party again.

Oneilneys latest post has it correct. I was looking for a picture of mine but don't have one. However, I did find another one online that better displays the connections. The wire colours in this photo match that of MY Thor setup. But NEVER take that for granted. Knowing Thor the way I do now, my colours may be very different than yours.

My next addition is the solid state coach battery disconnect. Same manufacturer of the BIM - called a BD225.

[revjeffrey]

Originally Posted by Oneilkeys

Looking at it again, it seems that the BIM160 might be the best replacement for the BIRD. It us rated for 160 continuous amps and the BIRD literature says it protects up to 150 positive amps.
The BIM does not have a generator connection so it makes it more straight forward. The relay core wire from the BIRD is not used - as ScottyB410 indicates that is internal in the BIM because it is a BIRD and Trombetta combined. The ignition wire goes to the ignition connection in the BIM and the Coach Battery to the Sig connection for the emergency start. I do not know if there is a fuse in that line to the emergency start, so I would put a 5 amp in that wire before I hooked it up to the BIM. In the Axis i am still not sure exactly how the emergency switch is set up, so I am interested to see what ScottyB410 has to say on this issue.
Good luck. I might buy one of these things just to have in my spare parts box.

I just open the front engine grill of my 2017 Axis and discovered. I already have a Bim?

[ScottyB410]

Yes you do!
That solves a lot of issues down the road (which is where they always fail). Never close to home!

[Oneilkeys]

Great! And as I suspected Thor used the BIM160 in the Axis. That should prevent a lot of problems in the future. The only negative is that all I learned about the BIRD/Trombetta is about as useful as how to fix a typewriter.

[revjeffrey]

Originally Posted by Oneilkeys

Great! And as I suspected Thor used the BIM160 in the Axis. That should prevent a lot of problems in the future. The only negative is that all I learned about the BIRD/Trombetta is about as useful as how to fix a typewriter.

How do you think I feel? Weeks and weeks of studying all of your posts all the sleepless nights worrying how am I going to hook up a Bim. I get to storage and put my battery in and find out I'm already a.... "Bimmer".

[JamieGeek]

Hey we have the BCC in ours so I can't even contribute to the BIRD/Trombetta discussions.

Although that BIM looks nice and compact I wonder if it would be difficult to replace/modify ours to use a BIM aside from the BCC (I know the BCC does a lot more than the BIRD/Trombetta/BIM does).

[bigben]

Well as Oneilkeys pointed out - I've learned a great deal about the Trombetta and BIRD that has some general knowledge usefulness but with a BIM life would get simpler. In post #22 above one the pics was intended to show how the colors were changed up going into the harness. Looking at the BIM 225, I am not sure I have a lead going to the emergency start switch so I would just leave that post empty. The other leads translate directly to the wiring on the BIM 225.

Looking for the PRECISION CIRCUITS BATTERY ISOLATION MGR 160 AMPs what I find are the 225s. I believe the 225 should be an acceptable substitute.

Thanks to everyone for all the knowledge gained on this thread - an amazing collection of experts. Thanks again.

[revjeffrey]

You were asking about a fuse on the Bim there is a fuse it's a 15 amp fuse here's the photo.

[bevedfelker]

Oneilkeys -- well how do you think I feel after all the research I did on the BIRD, Trombetta, BCC and then wrote it all up for the manual.

Now I guess I have to study the BIM and add a para on that too to the manual.

[Oneilkeys]

Originally Posted by bigben

Well as Oneilkeys pointed out - I've learned a great deal about the Trombetta and BIRD that has some general knowledge usefulness but with a BIM life would get simpler. In post #22 above one the pics was intended to show how the colors were changed up going into the harness. Looking at the BIM 225, I am not sure I have a lead going to the emergency start switch so I would just leave that post empty. The other leads translate directly to the wiring on the BIM 225.

Looking for the PRECISION CIRCUITS BATTERY ISOLATION MGR 160 AMPs what I find are the 225s. I believe the 225 should be an acceptable substitute.

Thanks to everyone for all the knowledge gained on this thread - an amazing collection of experts. Thanks again.

The 225 is the 160’s bigger brother. It costs about $20 more than the 160 but does the same thing.

[Oneilkeys]

Originally Posted by bevedfelker

Oneilkeys -- well how do you think I feel after all the research I did on the BIRD, Trombetta, BCC and then wrote it all up for the manual.

Now I guess I have to study the BIM and add a para on that too to the manual.

Looks like you’ve got some good stuff to start with. I was going to ask you if you were going to put it in your manual. Thanks again for your excellent work.

[bevedfelker]

The only thing that to me is different is that (if I'm reading it right) the BIM allows both battery sets to charge at the same time when one set requires charging. Is that right? So is there a BIRD? and if so, what's its purpose? Also the description says the BIM isolates one set from the other when a load is placed on one set to prevent it from drawing the other set down. So that complete description seems to nullify the need for a BIRD and Trombetta. Does that sound right?

The BIRD/Trombetta and/or BCC only allows the bank that needs charging to be charged. The isolation relay allows the system to change back and forth charging one battery set at a time.

[Oneilkeys]

Yes and no Ed. The BIM replaces the BIRD and Trombetta. It is a BIRD and Trombetta in one unit. It charges both batteries at the same time- just as the BIRD and Trombetta do. Both the BIM and the BIRD/Trombetta sense the charge on both battery banks and close the solenoid between the battery banks (connecting them) whenever the voltage on the battery bank that is not hooked directly to the charging system shows 13.1v. That will happen whenever either the alternator is running or shore power or the generator are in use. The BIRD will disconnect the two battery banks (open the solenoid) while the batteries are charging if they fall below 12.0v (so that the full charge goes into the chassis battery) but I can find nowhere that the BIRD or the BIM disconnect the battery banks if one or both is fully charged. The converter/charger drops the voltage down to 13.5 and 13.1 (if it is working properly) as the coach batterys become fully charged, but the alternator does not.