Most motorhomes use one of two prevalent systems. The older one is the Intellitec BIRD, see
https://intellitec.com/wp-content/up...-C-Rev-A-1.pdf.
The newer one is the Precision Circuits BIM, see
https://precisioncircuitsinc.com/pro...ion-manager-2/. PC also makes 225 amp versions and a lithium version. PC's BIM is considered to be more sophisticated than Intellitec's BIRD. The PC Li BIM has logic that minimizes heavy loads on the chassis alternator.
You should be able to hear either of them click in when you hit the aux start button, but that doesn't mean that the contacts are good, it only means that the solenoid is moving.
I have the BIM 160 on my 2021 Axis. It is located under the hood on the driver's side near the wheel well.
You should be able to find yours by having someone push the aux start button while you look underneath the hood.
David
Thor Forums
