Battery Monitoring System (BMS) Control Module

WARNING: This page is about a different car, the 2020 Jaguar XE and 2019 Jaguar XE. However, it is still accessible from the selected car via links, so may be relevant.

Courtesy of JAGUAR LAND ROVER NORTH AMERICA, LLC

The Battery Monitoring System (BMS) control module is located on the battery negative (-) terminal and is clamped to the terminal with a bolt and nut. The battery negative ground cable is connected to the BMS control module and is attached to a ground stud on the vehicle body.

The BMS control module is connected into the vehicle wiring harness via a multiplug. The BMS control module receives a 12V power supply direct from the battery positive terminal. A Local Interconnect Network (LIN) bus connection provides communication between the BMS control module, the BCM/GWM assembly and the Quiescent Current Control Module (QCCM) for control and monitoring of the battery current drain and state of charge.

The BMS control module measures the battery current and voltage, which it communicates to the BCM/GWM assembly over the LIN bus connection. The BCM/GWM assembly also receives generator output information on a LIN bus connection. Based on the information received from the BMS control module, the BCM/GWM assembly will control the output from the generator and request the switching off of electrical loads if necessary.

CAUTION: Due to the self-calibration routine, it is recommended that all power supply diagnostic testing is carried out using the Jaguar approved diagnostic system rather than a digital multimeter.

The BMS control module is able to generate DTCs to help diagnose battery or generator power supply issues. These DTCs can be read using the Jaguar approved diagnostic system. The Jaguar approved diagnostic system can also be used to implement a battery and generator self-test routine.

If a fault is detected, the BCM/GWM assembly and the ECM will override the BMS control module.

The BMS control module DTC's can be used to help diagnose battery or generator power supply faults. The DTC's are stored in BCM/GWM assembly. The Jaguar approved diagnostic system has a process for an automated power supply diagnostic procedure. The procedure provides a menu driven process to locate a fault in a logical sequence. The procedure uses the capability of the BMS control module and generator LIN bus controlled functions to provide current flow information and will detect if the BMS control module or generator are functioning correctly.