Battery Monitoring System

WARNING: This page is about a different car, the 2011 Jaguar XKR, 2011 Jaguar XK, 2010 Jaguar XKR, and 2010 Jaguar XK. However, it is still accessible from the selected car via links, so may be relevant.

Courtesy of JAGUAR CARS, INC.

The battery monitoring system module measures battery current and voltage, which it communicates to the central junction box (CJB) over a local interconnect network (LIN) bus connection. The central junction box (CJB) transmits the battery information to the instrument cluster over the medium speed controller area network (CAN) bus. The instrument cluster acts as a gateway between the medium and high speed controller area network (CAN) bus networks, and transmits the battery condition information to the engine control module (ECM) over the high speed controller area network (CAN) bus. Based on the information received from the battery monitoring system module, the engine control module (ECM) will control the output from the generator and request the switching off of electrical loads if necessary. Refer to Generator information.

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 battery monitoring system module is able to generate diagnostic trouble code (DTC)'s to help diagnose battery or generator power supply issues. These diagnostic trouble code (DTC)'s 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. See Battery .

If a fault is detected, the engine control module (ECM) will override the battery monitoring system module.

The battery monitoring system module diagnostic trouble code (DTC)'s can be used to help diagnose battery or generator power supply faults. The diagnostic trouble code (DTC)'s are stored in both the central junction box (CJB) and the engine control module (ECM). 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 battery monitoring system and generator local interconnect network (LIN) bus controlled functions to provide current flow information and will detect if the battery monitoring system or generator are functioning correctly.