Good for you, no one should be afraid to ask a question but should expect a responsible answer.
The BMS system will automatically detect the new battery's capacity, you need to do nothing. Remember to connect any accessories to your battery, if you have any, on the non-battery post side of the BMS sensor so the sensor can detect the usage of power from the battery. I think late-model RAMs moved the sensor to the negative post to mitigate this issue. I believe the owner's manual or perhaps it was the up-fitters guide that mentions this.
As far as Scotty Kilmer, I would file him in the entertainment column and not in the expert column.
There is no BMS in a Ram, there is an IBS.
The documents I see show it does in fact have memory.
If you used one of those "power saves devices" to swap the battery you would be wrong for doing so and would screwup the new battery since the IBS doesn't reset.
The Intelligent Battery Sensor (IBS) (1) is a device used to measure battery current, voltage, and temperature whose outputs are used in the energy management strategy.
The mechanical portion of the IBS is comprised of the battery clamp for the negative terminal and a captured bolt to attach the ground cable to. The functional tasks include establishing the electrical contact between the body and the negative battery post, housing the electronic module (actual sensor element) and the provision of an adequate thermal contact between the sensor system temperature sensor and the negative battery post. The mechanical portion of the IBS also protects the sensitive electronic components from external influences.
The IBS is mounted directly on the 12 volt DC battery’s negative post. The battery post clamp nut is a captive nut and the stud will break if the nut is removed.
OPERATION
The Intelligent Battery Sensor (IBS) contains a low value resistor, or shunt. The shunt creates a voltage drop, which is read by an internal microcontroller to determine the current flow in and out of the battery. In addition to the shunt, the IBS contains a sensor to monitor the battery’s temperature. Data gathered by the IBS, including temperature, voltage, and current measurements, are transmitted over a Local Interface Network (LIN) communication bus to either the Body Control Module (BCM) or the Powertrain Control Module (PCM), depending on the application. The IBS serves two primary purposes. The first is to provide the PCM with both immediate and historical battery information, so the PCM can precisely control the charging system. Precise charging is important on a vehicle equipped with an Absorbent Glass Material (AGM) battery, because they are especially sensitive to overcharging. The second purpose is to provide data to the BCM for operation of the load-shedding feature. A fused power circuit and the LIN bus are connected to the IBS though a two-terminal connector.
The IBS is readable and diagnosable via the diagnostic scan tool. The tool can display all of the available parameters needed for vehicle servicing or troubleshooting.
In addition to real-time measurements, the IBS transmits some calculated battery data over the LIN bus. These values are calculated by storing measurements over time.
Information the IBS sends on the Controller Area Network-Interior High Speed (CAN-IHS):
- SOC = Battery State of Charge (or SOC): Is expressed as a percentage. The IBS calculates the SOC based on measured voltage, and charge and discharge rates. Therefore, SOC is not a direct percentage of battery voltage.
- SOF = Battery State of Function (SOF): Is a calculated prediction of the lowest voltage the battery will drop to during engine cranking. This calculation is based off of ambient temperature and vehicle load. If the conditions are not correct the system will go into “ Battery Protection Mode” which should be displayed on the Instrument Cluster Panel (ICP).
The PCM and BCM use this calculated information to optimize vehicle power management for increased fuel efficiency.
When the IBS is powered up for the first time or is powered after a power disconnection, it enters a “re-calibration” phase, where the IBS must recognize the type of battery and its characteristics and state. So in this phase the tolerances on the state functions (SOC, SOF) are greater than in normal working condition. When IBS is disconnected from the battery, the device loses its stored memory. When power is restored, the IBS starts a relearn process. Until the relearn process is complete, accurate battery state information is unavailable to other vehicle systems. The IBS relearn process requires three to five normal, operator initiated starts with at least eight hours of engine off time between each start. Usually, the process takes a few days of vehicle operation to complete. Remember, the relearn process is restarted every time power is reconnected to the IBS. This has a major effect on the stop/start feature.
A Note about Electric Stop/Start (ESS) and the IBS - ESS operation places a heavy demand on the battery. So, during ESS events, the PCM boosts the charging system’s output to immediately recharge the battery after a start.
If the IBS is faulty it cannot be serviced, it must be replaced.
BATTERY DISCONNECT AND CONNECT - SINGLE 12V BATTERY SYSTEM
NOTE
The graphic in this procedure depicts a typical negative battery cable and Intelligent Battery Sensor (IBS) connection at the negative battery post. The location of the battery and orientation of the cable eyelet connection to the IBS can vary between vehicles. Refer to the Description and Operation for the battery specific location.
1 - Ground Terminal Nut |
2 - IBS Wire Harness Connector |
BATTERY DISCONNECT PROCEDURE:
- Remove the ground terminal nut.
- Remove and isolate the negative battery cable eyelet from the IBS. This will isolate the 12 volt from the vehicle electrical system.
NOTE
If removing the negative battery cable clamp from the battery post instead of removing the negative battery cable eyelet, the Intelligent Battery Sensor (IBS) wire harness connector must be disconnecting prior to removing the cable end. Failure to disconnect the IBS wire harness connector can lead to damage of the IBS wire harness connector.