Notes on intelligent battery sensor (IBS)

2023 BMW M240iSECTION Notes on intelligent battery sensor (IBS)
NOTE: Do not connect the charger to the 12 V charging socket

The 12 V charging socket is supplied with voltage by the rear power distribution box via relay. This relay drops out after terminal 15 OFF. This means that a battery maintainer connected at the 12 V charging socket will be disconnected from the battery. Only charge the battery via the jump start terminal. Only then can the voltage supply be registered by the vehicle.

WARNING: Danger of destruction in event of mechanical strain
  • Do not introduce any additional connections at the battery negative terminal.
  • Do not modify the grounding cable. The ground cable also serves heat dissipation.
  • Do not establish any connection between the IBS and the sensor screw.
  • Do not use force when disconnecting the terminal cover from the battery terminal:
    • Do not pull on the ground cable.
    • Do not place any tools under the IBS to lever off the terminal cover.
  • Do not use IBS connections as levers.
  • Use a torque wrench and set tightening torque in accordance with repair instructions.
  • Do not release or tighten down sensor screw (Torx screw).
  • Avoid contact between IBS and ground.
WARNING: Danger of destruction to IBS and wiring upon battery replacement
  • The IBS and wiring can be destroyed by mechanical strain upon battery replacement. Therefore avoid mechanical strain.
  • The size (capacity) of the battery required for the car is coded in the Car Access System (CAS).
  • Use the battery size (capacity) installed standard upon battery replacement.
  • Recode the Car Access System (CAS) when installing a battery with a different capacity.
  • Register battery replacement via service functions in diagnostic system.
  • Delete fault code entries in the Digital Engine Electronics (DME) associated with battery replacement.
  • Always proceed in accordance with the repair instructions.
NOTE: Battery draining possible in spite of the intelligent battery sensor IBS being fault-free.
  • A battery can be drained (e.g. with lights or radio switched on) even when the IBS functions perfectly in conjunction with power management.
  • For this reason, only exchange the IBS when there is a corresponding fault code entry!Β 
RENDER: 1.0x

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