Land Rover Defender: Audio System - Operation

The IGM / ICCM is subject to the power management of the quiescent current relay which is integrated into the Rear Junction Box (BCMB). Power management is controlled by the BCM/ GWM.

The BCM/ GWM controls the quiescent current relay in the BCMB. The BCM/ GWM receives startup battery status signals transmitted by the Battery Monitoring System (BMS) control module. The BCM/ GWM assembly can disable the power supply to other non-essential control modules to avoid excessive discharge of the startup battery. The system supplied through the quiescent current relay is the infotainment system.

The IGM / ICCM is connected to the FCDIM through an APIX2 connection. APIX2 is a high speed data transmission over 2 twisted pair cables. FCDIM selections by the driver are passed to the IGM / ICCM on the APIX2 connection for processing.

The front portable media interface panel is connected to the IGM / ICCM with USB data links. The USB sockets provides a 5V charging output for the connected device and also provides external connection of a device to the IGM / ICCM. Power is supplied to the portable media interface panel from a fuse in the Rear Junction Box through the quiescent current relay.

The AAM receives a power supply through a fuse in the Rear Junction Box.

Video data is passed from the IGM / ICCM to the IPC on APIX2 connection. The data connection provides video output from the IGM / ICCM for user interface information to be displayed in the IPC.

ACTIVE SOUND DESIGN

NOTE: The active sound design feature is only available on specific powertrains.

Active sound design is an enhancement of the vehicle engine sound, reproduced and emitted over the vehicle speaker system.

The PCM provides engine speed input for the AAM. The engine speed signal is a Pulse Width Modulated (PWM) signal. The engine speed input allows the AAM to provide a digital audio enhancement of the engine sound.

The PCM also outputs signals for:

• Engine torque
• Road speed
• Power Mode.

The PCM sends these signals to the BCM/ GWM on the FlexRay. The BCM/ GWM sends these signals to the IGM / ICCM. The signals are sent through HS CAN HMI systems bus.

The AAM contains software to operate the enhanced engine sound output.

The enhanced engine sound output over the vehicle speakers is active when the engine is in Power Mode 7 (engine running). The sound remains active even when the audio volume is at 0 or infotainment system is turned OFF. There is no customer interaction with the system which is always active.

The PCM and the AAM record Diagnostic Trouble Code (DTC)s when a fault occurs. The JLR approved diagnostic equipment reads the fault information.

The active sound design software is not installed in a replacement AAM. It is necessary to install the software in the replacement AAM to use the JLR approved diagnostic equipment.

When the incorrect software is installed in the AAM, a loud engine noise may be heard.

DIAGNOSTICS

The IGM / ICCM records any DTC and related data. The DTC and related data are read using the JLR approved diagnostic equipment.

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

CONTROL DIAGRAM

CONTROL DIAGRAM - 1 OF 1

A = HARDWIRED: O = LIN: T = CO-AXIAL: AT = USB: AU = APIX2: AW = BROADR-REACH ETHERNET: AX = FLEXRAY: BA = HS CAN HMI SYSTEMS BUS.

1. IGM / ICCM
2. BCM/ GWM
3. Vehicle speakers
4. AAM
5. PCM - Vehicle speed
6. IPC
7. Head Up Display (HUD)
8. FCDIM
9. Ground
10. Power supply
11. Global Navigation Satellite System (GNSS) signal splitter
12. Roof pod - GNSS antenna
13. Roof pod - SDARS (if equipped)
14. Antenna amplifier (number dependant on vehicle and system specification)
15. Bluetooth/WiFi antenna (quantity 2)
16. SWM
17. Left steering wheel switch
18. Front portable media interface panel
19. PCM - Engine signals

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