Dual Battery System - Dual Battery System Vehicles Only: Notes

WARNING: This page is about a different car, the 2015 Jaguar XF, 2014 Jaguar XF, and 2013 Jaguar XF. However, it is still accessible from the selected car via links, so may be relevant.

The dual battery system prevents electrical loads on the vehicle being subjected to low voltage levels during an ECO (stop/start system) engine start. Low voltage can occur due to the power demand of the TSS (Tandem Solenoid Starter) motor and could result in degraded performance of components and/or system control modules. The GWM contains the software to control the dual battery system and electrical load management system to ensure that ECO engine starts do not affect other vehicle systems.

The dual battery system isolates all power supply sensitive electrical components which may be affected by low voltage from the primary battery due TSS motor operation, and supplies them with power from the secondary battery when an engine start is in progress.

The DBJB (Dual Battery Junction Box) contains two contactors, which operate to change the power supply into two separate circuits when an ECO engine start is required. Sensitive electrical components are supplied from the secondary battery. The primary battery power is used exclusively to supply the TSS motor and maintain essential power loads to the engine management system required for engine starting. The contactors are operated by the DBM (Dual Battery Module) on receipt of LIN bus information from the GWM.