Land Rover Defender: Generator - Description and Operation

DESCRIPTION AND OPERATION

COMPONENT LOCATION

COMPONENT LOCATION - 1 OF 1

1. Generator
2. Electrical connector - Body Control Module/Gateway Module (BCM/GWM)
3. Electrical connector - Startup battery Positive connection

OVERVIEW

When in Power Mode 7 (engine running), the generator produces an Alternating Current (AC) which is converted to a Direct Current (DC) internally. The output voltage from the generator is controlled by the regulator which is located inside the generator. The output voltage is supplied to the Positive of the startup battery through the Auxiliary Junction Box (AJB) and the Battery Junction Box (BJB).

DESCRIPTION

GENERATOR

The generator is installed on the front left of the engine. The generator produces electrical power for the electrical system and charges the startup battery. The generator is driven by the accessory drive belt. The Body Control Module /Gateway Module (BCM/GWM) controls the generator through the Local Interconnect Network (LIN).

When the communication between the generator and the BCM/GWM is lost, the generator generates at a default voltage. The default voltage is 13.5V or 13.8V (depending on the specific generator variant). In order to instigate the default mode, the generator needs to be initially spun above 3,000 Revolutions Per Minute (RPM).

BATTERY MONITORING SYSTEM CONTROL MODULE

The Battery Monitoring System (BMS) control module is located on the Negative terminal of the startup battery. The BMS control module monitors the temperature, current, voltage, current drain and charge state of the startup battery.

The BMS control module is connected with the Body Control Module/Gateway Module (BCM/GWM) through the Local Interconnect Network (LIN). The BMS control module constantly receives information from the BCM/GWM regarding the vehicle state and electrical loading. The BMS control module contains software maps that provide a mathematical model of the startup battery conditions.

OPERATION

The charging system consists of a generator, a Battery Monitoring System (BMS) control module and a Body Control Module/Gateway Module (BCM/GWM). The generator generates electrical power for the vehicle electrical system and maintains the startup battery in a charged state. The rate of charge for the startup battery is controlled by the BCM /GWM.

Both the generator and BMS control module are connected to the BCM/GWM through the Local Interconnect Network (LIN). The BCM/GWM receives the information from the BMS control module regarding the startup battery conditions.

The BCM/GWM sets the target voltage according to the information from the BMS control module. The charging voltage range is 12.3V to 14.8V.

The LIN also communicates a mechanical failure, or fault in the wiring harness and connections between the generator and the BCM/GWM. A Diagnostic Trouble Code (DTC) is stored in the BCM/GWM. When necessary, the charge warning indicator illuminates in the Instrument Cluster (IC) in the event of a fault.

During engine starting, the charge warning indicator illuminates in the IC in Power Mode 6 (ignition ON) and below.

The charge warning indicator extinguishes in Power Mode 7 (engine running) when the BCM/GWM detects a generator output voltage.

SMART CHARGING SYSTEM

The smart regenerative charging system increases the generator output when the vehicle brakes or decelerates. The smart regenerative charging system converts the kinetic energy of the vehicle into electric energy without additional fuel.

The smart regenerative feature operates within certain environmental constraints to make sure that the feature delivers the greatest benefit possible while maintaining system integrity.

The regenerated electric energy is captured by charging the startup battery above the target level. The electrical systems use the electric energy at a later stage. This could be when the engine is switched OFF during a stop-phase, or when the generator operates in a less efficient mode.

The startup battery State of Charge can be corrected up or down. This allows the system to achieve the most appropriate level to maximize the benefit of the smart regenerative charging feature. When the Body Control Module /Gateway Module (BCM/GWM) decides there is recoverable energy available, then the generator charge set-point is overridden.

The purpose of this system is the generator does not constantly charge the startup battery in circumstances such as:

• When there is high torque load on the engine.
• When the vehicle is on a long motorway journey.

The BCM/GWM allows the generator to put more voltage than normal in the startup battery. When the driver puts a high torque load on the engine, the BCM/GWM checks what the load is on the electrical system. When the electrical load is within parameters, the BCM/GWM decreases the quantity of charge it puts into the startup battery. To do this, the BCM/GWM decreases the voltage and rate of charge. The BCM/GWM can also stop charging the battery. These actions decrease:

• The load on the engine
• Fuel consumption
• Emissions.

When the torque load on the engine decreases, the BCM/GWM increases the quantity of charge that goes into the startup battery.

The BCM/GWM constantly monitors all active electrical loads and changes the output of the generator to match. The operation of the system is not visible to the driver.

DIAGNOSTICS The Body Control Module/Gateway Module (BCM/GWM) records any Diagnostic Trouble Codes (DTCs) and related data. Read the DTCs and related data with the Jaguar Land Rover (JLR) approved diagnostic equipment.

The JLR approved diagnostic equipment enables certain components to be activated and also live data to be read.

CONTROL DIAGRAM

CONTROL DIAGRAM - 1 OF 1

A = HARDWIRED: O = LOCAL INTERCONNECT NETWORK (LIN): BA = HIGH SPEED (HS) CONTROLLER AREA NETWORK (CAN) HUMAN MACHINE INTERFACE (HMI) SYSTEMS BUS.

1. Body Control Module/Gateway Module (BCM/GWM)
2. Instrument Cluster (IC)
3. Generator
4. Ground
5. Power supply
6. Battery Monitoring System (BMS) control module

DIAGNOSIS AND TESTING

PRINCIPLES OF OPERATION

REFER to: Charging System (Battery and Charging System - General Information, Diagnosis and Testing).

For a detailed description of the generator and regulator system and operation, refer to the relevant description and operation section of the workshop manual. REFER to: Generator (Generator and Regulator - INGENIUM I4 2.0L Diesel, Description and Operation).

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