Instrument Panel, Gauges and Warning Indicators: Description and Operation
Instrument Cluster
COMPONENT LOCATION - UK
NOTE: The 'Rest of World' instrument cluster is the same as the UK instrument cluster but does not have a miles per hour (mph) scale on the speedometer.
COMPONENT LOCATION - NORTH AMERICA
OVERVIEW
The instrument cluster is located in the instrument panel, above the steering column. The instrument cluster comprises analogue gages and a number of warning indicator lamps to display system status. High line instrument clusters also feature a Liquid Crystal Display (LCD) message center to provide vehicle operation details to the driver. The message center is located in a central position in the high line instrument cluster. Low line instrument clusters feature warning indicator lamps in place of the message center.
ANALOGUE GAGES
Tachometer
The tachometer is located on the Left Hand (LH) side of the instrument cluster and displays engine speeds of up to 8000 Revolutions Per Minute (RPM) on petrol variants, and 6000 RPM on diesel variants. The tachometer is driven by an engine speed signal, which originates from the Crankshaft Position (CKP) sensor. This signal is transmitted over the high speed Controller Area Network (CAN) bus by the Engine Control Module (ECM). The Central Junction Box (CJB) acts as a gateway and transmits the engine speed signal to the instrument cluster on the medium speed CAN bus. The signal is received by the instrument cluster microprocessor and the output from the microprocessor drives the tachometer.
Engine Temperature Gage
The engine temperature gage is located in the center of the instrument cluster and is driven by medium speed CAN bus messages from the CJB. The CJB receives an Engine Coolant Temperature (ECT) signal from the ECM over the high speed CAN bus when the vehicle enters power mode 6 (ignition on). The needle pointer position translates to the following approximate temperatures.
If the ECT signal rises above 118 degrees C (244degrees F) on diesel vehicles, or 127 degrees C (260 degrees F) on petrol vehicles, the instrument cluster will illuminate the high ECT warning indicator. If the instrument cluster fails to receive an ECT signal from the CJB, the engine coolant temperature gage will move to the 'end of hot' position and the warning indicator will be illuminated.
Fuel Level Gage
The fuel level gage is located in the center of the instrument cluster and displays fuel tank contents when the vehicle is in power mode 6. When the ignition is switched off, the pointer returns to the park position.
Two Magnetic Passive Position Sensors (MAPPS) are located in the saddle type fuel tank, one on either side. The resistance values for both sensors are measured by the CJB through a series of hardwired connections. The CJB converts both values to medium speed CAN messages for delivery to the instrument cluster. The instrument cluster uses the 2 CAN bus messages to calculate the total amount of fuel in both halves of the tank. The instrument cluster will also damp the total fuel value to eliminate constant pointer movement due to fuel moving in the tank.
The following table shows the approximate fuel tank level and the respective needle pointer position.
If the instrument cluster fails to receive the fuel level signals from the CJB the fuel level gage will move to the empty position and the low fuel level indicator will be illuminated.
Speedometer
The speedometer is located on the Right Hand (RH) side of the cluster and is available in 3 variants:
^ Major scale mph, minor scale kilometers per hour (kph)
^ Major scale kph, minor scale mph
^ Major scale kph only.
The speedometer is driven by medium speed CAN bus signals transmitted by the CJB. The vehicle speed signal is provided to the CJB by the Anti-lock Brake System (ABS) module over the high speed CAN bus and is an average of all 4 wheel speed sensor signals.
The speedometer also incorporates the odometer.
WARNING INDICATORS
The low line instrument cluster contains 39 indicators, the high line instrument cluster 27. The indicators in high line instrument clusters are supplemented by messages in the message center.
The warning indicators can be split into 2 groups; self controlled and externally controlled. Self controlled warning indicators are dependent on software logic within the instrument cluster for activation. Externally controlled indicators are supplied with current from another system controlling module or illuminated by the instrument cluster on receipt of a medium speed CAN bus message from the CJB.
Ignition/No Charge Indicator
The ignition/no charge indicator is controlled by the instrument cluster software and illuminated by medium speed CAN bus signals from the ECM via the CJB. The indicator illuminates in a red color when the vehicle enters power mode 6 and is extinguished when the engine is started.
If the indicator remains illuminated after the engine has started or illuminates when driving, the alternator charge output has failed.
Low Oil Pressure Warning Indicator
The low oil pressure warning indicator is illuminated by the instrument cluster on receipt of a medium speed CAN bus signal from the CJB. The signal originates in the ECM and is generated by the engine oil level sensor on petrol vehicles and the engine oil pressure sensor on diesel vehicles.
The indicator illuminates in a red color when the vehicle enters power mode 6 for a 3 second bulb check. If the bulb subsequently illuminates when the engine is running, the engine should be stopped immediately it is safe to do so.
Malfunction Indicator Lamp
The Malfunction Indicator Lamp (MIL) is illuminated by the instrument cluster on receipt of a medium speed CAN bus signal from the CJB. The signal originates in the ECM and is generated if an On-Board Diagnostic (OBD) fault has been detected which will cause excessive emissions output. This may relate to either an engine management or transmission fault.
The MIL is illuminated in an amber color when the vehicle enters power mode 6 for a 3 second bulb check. The bulb check in this instance is carried out by the ECM via the CJB, not the instrument cluster. If the MIL subsequently illuminates the vehicle should be interrogated using the Land Rover approved diagnostic system at the earliest opportunity.
Safety Belt Warning Indicator
The safety belt warning indicator will illuminate in a red color on receipt of a medium speed CAN bus signal from the CJB. The signal originates in the Restraints Control Module (RCM), which monitors the status of the occupant classification system and switches located in the safety belt buckles.
Three variations of warning are available depending on vehicle configuration:
^ Reminder (all vehicles except North American Specification (NAS) vehicles)
^ Federal Motor Vehicle Safety Standard (FMVSS) 208 reminder (NAS vehicles only)
^ Belt Minder
The conditions for safety belt warning indicator illumination are as follows:
Reminder
^ Vehicle in power mode 6
^ Drivers safety belt not secured in its buckle
^ Large passenger detected in front passenger seat with an unsecured safety belt.
The warning indicator will remain illuminated until either the ignition is switched off or conditions 2 and 3 no longer exist.
FMVSS-208 Reminder
^ Vehicle in power mode 6
^ Drivers safety belt not secured in its buckle.
The warning indicator will remain illuminated for 65 seconds and will be accompanied by a single 6 second chime from the instrument cluster sounder.
NOTE: The warning indicator and chime will not activate if these conditions arise 75 seconds after the vehicle has entered power mode 6.
The warning indicator will be extinguished and the sounder cancelled if the ignition is switched off or the driver's safety belt is secured in its buckle.
Belt Minder
^ Vehicle in power mode 6 (all vehicles except NAS vehicles)
^ Vehicle in power mode 6 for 75 seconds (NAS vehicles only)
^ Vehicle speed is greater than 6 mph (10 kph)
^ Drivers safety belt not secured in its buckle
^ Large passenger detected in front passenger seat with an unsecured safety belt.
The warning indicator will flash at a frequency of 2 Hz while accompanied by a chime from the instrument cluster for 10 seconds. This is followed by a 10 second period where the warning indicator is permanently illuminated and the sounder is silent. This 10 second cycle will be repeated for a maximum of 190 seconds or any of the conditions listed above cease to exist.
Supplemental Restraint System Warning Indicator
The Supplemental Restraint System (SRS) warning indicator is illuminated on receipt of a medium speed CAN bus signal from the CJB. The signal originates in the RCM which monitors the condition of the SRS and illuminates the red warning indicator accordingly.
The SRS warning indicator is illuminated by the RCM for a 6 second bulb check when the vehicle first enters power mode 6. If a fault is detected with the indicator, the instrument cluster returns a medium speed CAN bus signal via the CJB to the RCM and a Diagnostic Trouble Code (DTC) is stored in the RCM's memory. The message 'SRS' will also be displayed in the odometer.
Left and Right Hand Turn Signal Indicators
The green left and right hand turn signal indicators are illuminated on receipt of medium speed CAN bus signals from the CJB. The CJB provides a CAN bus signal with one of the following values:
^ 0 - LH steering column multi-function switch in the central position
^ 1 - LH steering column multi-function switch in the LH turn position
^ 2 - LH steering column multi-function switch in the RH turn position
^ 3 - Hazard flashers requested.
If the vehicle is in power mode 6 the instrument cluster will flash the appropriate turn signal indicator if a medium speed CAN bus signal is received with a value of 1 or 2. Medium speed CAN bus signals with a value of 3 will activate both the LH and RH turn signal indicators simultaneously irrespective of power mode.
When activated, the left and right hand turn signal indicators will be accompanied by 'tick tock' chimes from the instrument cluster sounder.
Brake Warning Indicator
EBA and EBD warnings are transmitted to the CJB from the ABS module over the high speed CAN bus. These signals are relayed to the instrument cluster on the medium speed CAN bus and will activate the brake warning indicator when the vehicle is in power mode 6. If an EBA warning is requested, the indicator will illuminate in an amber color. If an EBD warning is requested, the indicator will illuminate in a red color.
Low brake fluid level warnings are also transmitted to the instrument cluster from the CJB on the medium speed CAN bus. The signal originates in the ABS module which receives a hardwired input from the brake fluid level sensor. If a low brake fluid warning is requested, the indicator will illuminate in a red color when the vehicle is in power mode 6.
The brake warning indicator is also subject to a 3 second bulb check when the vehicle first enters power mode 6. The indicator will illuminate in a amber color for 1.5 seconds then a red color for 1.5 seconds.
High Engine Coolant Temperature Warning Indicator
The red high Engine Coolant Temperature (ECT) warning indicator is controlled by the engine temperature gage software.
Headlamp High Beam Indicator
The blue headlamp high beam indicator is illuminated on receipt of a medium speed CAN bus signal from the CJB. The signal originates in the light switch module and is transmitted to the CJB over the LIN bus. The instrument cluster will only illuminate the headlamp high beam indicator when the vehicle is in power mode 6 and the LH steering column multifunction switch is moved to the high beam position.
Tire Pressure Monitoring System Indicator
The Tire Pressure Monitoring System (TPMS) indicator is controlled by the instrument cluster on receipt of medium speed CAN bus signals from the CJB. The signal originates in the TPMS module. The indicator is illuminated in an amber color for a 3 second bulb check by the TPMS module when the vehicle enters power mode 6. If the indicator remains illuminated or flashes after the engine is started or when driving, the TPMS has developed a fault. The tire pressures should be monitored manually until the fault is rectified.
Anti-lock Brake System Warning Indicator
The Anti-lock Brake System (ABS) warning indicator is controlled by the ABS module which transmits a high speed CAN bus message to the CJB. The CJB relays the message to the instrument cluster over the medium speed CAN bus. The warning indicator is illuminated in an amber color for 3 seconds for a bulb check by the ABS module when the vehicle enters power mode 6. If the warning indicator remains illuminated or illuminates when driving, an ABS fault has occurred and the ABS function will not be available.
During the bulb check, if the warning indicator comes on for 0.5 second, then goes off for 0.5 second and is then illuminated for the remaining 2 seconds of the bulb check, this indicates that faults are stored in the ABS module memory.
If the warning indicator was illuminated due to a wheel speed sensor fault, the indicator will remain illuminated at the next ignition cycle, even if the fault is rectified. When the vehicle is driven above a speed of 20 km/h (12.5 mph) the indicator will be extinguished. This allows the ABS module to perform a thorough check of the system and to establish that the output from the replaced sensor is correct.
Low Fuel Level Indicator
The low fuel level indicator is controlled by the fuel level gage software (see above). When the vehicle enters power mode 6, the low fuel indicator is illuminated in an amber color for a 3 second bulb check. If the fuel level gage software determines the low fuel indicator should be illuminated, it flashes the indicator at a rate of 2 Hz for 5 seconds. The first flash is accompanied by a chime from the instrument cluster sounder. After the 5 second flashing period the indicator will remain illuminated until fuel is added to the tank or the vehicle ignition is switched off.
Parking Brake Indicator
The red parking brake indicator is illuminated on receipt of a medium speed CAN bus signal from the CJB. The signal originates in the parking brake microswitch, which is hardwired to the CJB. The parking brake indicator will only illuminate if the parking brake is applied and the vehicle is in power mode 6.
Rear Fog Lamp Indicator
The rear fog lamp indicator is illuminated on receipt of a medium speed CAN bus signal from the CJB. The indicator is illuminated in an amber color if the vehicle is in power mode 6 and rear fog lamp operation has been requested.
Front Fog Lamp Indicator
The front fog lamp indicator is illuminated on receipt of a medium speed CAN bus signal from the CJB. The indicator is illuminated in a green color if the vehicle is in power mode 6 and front fog lamp operation has been requested.
Adaptive Front Lighting System Indicator
The Adaptive Front lighting System (AFS) indicator is controlled by the AFS module. The AFS module is hardwired to the CJB, which relays signals to the instrument cluster over the medium speed CAN bus. When the vehicle enters power
mode 6, the AFS indicator is illuminated in an amber color for a 3 second bulb check. If during AFS operation a fault is detected, the AFS indicator will flash at a frequency of 2 Hz.
Speed Control Indicator
The speed control indicator is controlled by the ECM, which transmits a speed control active signal to the instrument cluster via the CJB. The indicator will illuminate in an amber color when the vehicle is in power mode 6 and speed control is active.
Trailer Indicator
The trailer indicator is controlled by the instrument cluster on receipt of medium speed CAN bus signals from the CJB. When a trailer is connected to the vehicle electrical system and the turn signal indicator switch is operated, the CJB transmits a signal to the instrument cluster to operate the trailer indicator. The instrument cluster software controls the flash rate of the indicator which flashes in a green color. The trailer indicator flashes slowly, at the same rate as the turn signal indicators.
Low Washer Fluid Indicator
The low washer fluid indicator is illuminated on receipt of a medium speed CAN bus signal from the CJB. The signal originates in the low washer fluid level switch, which is hardwired to the CJB.
The amber low washer fluid indicator is subject to a 3 second bulb check when the vehicle enters power mode 6. If a low washer fluid level is detected for more than 15 seconds when the vehicle is in power mode 6, the instrument cluster will illuminate the indicator.
Low Engine Coolant Level Warning Indicator
The low engine coolant level warning indicator is illuminated on receipt of a medium speed CAN bus signal from the CJB when the vehicle is in power mode 6. The signal originates in the ECM, which transmits the signal to the CJB over the high speed CAN bus.
When the vehicle enters power mode 6, the amber low engine coolant level warning indicator is illuminated for a 3 second bulb check. If the warning indicator remains illuminated after this period, the engine cooling system should be checked for leaks and topped up as necessary.
Transmission Warning Indicator
The transmission warning indicator displays automatic transmission and active-on demand coupling warnings. The warning indicator is illuminated on receipt of medium speed CAN bus signals from the CJB. The signals originate in the Transmission Control Module (TCM) and the active-on demand coupling control module respectively and are transmitted to the CJB over the high speed CAN bus.
The transmission warning indicator is a dual color indicator, which is subject to a 3 second bulb check when the vehicle enters power mode 6. For the first 1.5 seconds of the bulb check the indicator illuminates in an amber color, followed by 1.5 seconds illuminated in a red color.
The table below details warning indicator color against message center message.
Hill Descent Control Fault Warning Indicator
The amber Hill Descent Control (HDC) warning indicator is illuminated on receipt of medium speed CAN bus signals from the CJB.The signals originate in the ABS module and are transmitted to the CJB over the high speed CAN bus.
When the vehicle enters power mode 6, the HDC warning indicator is subject to a 3 second bulb check. If during HDC operation the HDC warning indicator illuminates it signifies that the 'fade out' strategy has been invoked due to component failure.
If the HDC warning indicator flashes it signifies that the 'fade out' strategy has been invoked due to brake system overheat. In this instance, the first flash is accompanied by a chime from the instrument cluster and the green HDC active indicator will be extinguished.
Door Open Indicator
The door open indicator is illuminated on receipt of medium speed CAN bus signals from the CJB. The signals originate in the door modules, which are hardwired to the CJB. The door open indicator will illuminate in a red color if a door open signal is received by the CJB from any door module while the vehicle is in power mode 6.
Engine Management System Warning Indicator
The engine management system warning indicator is illuminated on receipt of medium speed CAN bus signals from the CJB. The signals originate in the ECM and are transmitted to the CJB over the high speed CAN bus.
The amber engine management system warning indicator is illuminated for a 3 second bulb check when the vehicle enters power mode 6. If the indicator subsequently illuminates a DTC will be logged in the ECM which should be interrogated using the Land Rover approved diagnostic system.
Side Lamp Indicator
The green side light indicator is illuminated on receipt of a medium speed CAN bus signal from the CJB. The signal originates in the light switch module and is transmitted to the CJB over the Local Interconnect Network (LIN) bus. The instrument cluster will only illuminate the side lamp indicator when the vehicle is in power mode 6.
Dynamic Stability Control Indicator
The Dynamic Stability Control (DSC) indicator is illuminated by the instrument cluster on receipt of medium speed CAN bus signals from the CJB. The signal originates in the ABS module. The indicator is illuminated in an amber color for 3 seconds for a bulb check when the vehicle enters power mode 6. If no faults exist, the indicator is extinguished after the bulb check period.
When DSC is active, the indicator flashes to inform the driver that the system is regulating engine output and braking forces. If the indicator remains illuminated after the bulb check period or illuminates when driving, the DSC system has a fault or DSC has been deselected by the driver using the DSC switch on the floor console.
Hill Descent Control Active Indicator
The HDC active indicator is illuminated by the instrument cluster on receipt of medium speed CAN bus signals from the CJB. The signal originates in the ABS module. The indicator is illuminated in a green color when HDC is active and the vehicle speed is below a predetermined threshold. If the vehicle speed is faster than the threshold limit, the HDC indicator will flash until the vehicle speed is reduced. On high line instrument clusters a supporting message will also be displayed in the message center.
If the use of HDC causes the brake discs to exceed their pre-determined temperature, the HDC system initiates a 'fade out'. The HDC indicator flashes during 'fade out' and on high line instrument clusters a supporting message is displayed in the message center. When the brake discs have cooled sufficiently, HDC is reactivated and the HDC indicator is permanently illuminated.
Anti-theft Alarm Indicator
The anti-theft alarm indicator is controlled directly from the CJB via a hardwired connection. There is no software functionality within the instrument cluster to control operation of the anti-theft alarm indicator.
Glow Plug Indicator
The glow plug indicator is illuminated on receipt of a medium speed CAN bus signal from the CJB. The signal originates in the diesel ECM and indicates the glow plugs are operational. The indicator will illuminate in an amber color when the vehicle enters power mode 6 and a glow plugs active signal is received from the ECM. When the combustion pre-heat procedure has been carried out, the ECM informs the instrument cluster to extinguish the glow plug indicator.
Overspeed Warning Indicator
The amber overspeed warning indicator is illuminated on receipt of a medium speed CAN bus signal from the CJB when the vehicle is in power mode 6. The vehicle speed signal originates in the ABS module and is the same as that used by the speedometer.
The instrument cluster will flash the overspeed warning indicator at a rate of 2 Hz for 5 seconds if a speed of greater than 75 mph (120 kph) is reached. The first flash of the indicator will be accompanied by a chime from the instrument cluster. If the vehicle stays at this speed, the indicator will remain illuminated after the 5 second flashing period. The instrument cluster will extinguish the indicator if vehicle speed drops below 71 mph (114 kph).
CAR CONFIGURATION FILE
The car configuration file contains all relevant data about the specification and market condition of the vehicle, immobilization codes and driver personal settings. The master repository for this information is the CJB, with a back up being held in the instrument cluster. The information is continuously transferred between the 2 components to ensure the data is constantly backed-up.
CAUTION: When a new instrument cluster is to be installed, the Land Rover approved diagnostic system must be connected to the vehicle and the instrument cluster renewal procedure followed. This will ensure that vehicle coding data is correctly installed in the new instrument cluster. The Land Rover approved diagnostic system will also record the current service interval data and restore the settings in the new instrument cluster.
When a new instrument cluster is installed, the Land Rover approved diagnostic system is used to transfer the car configuration file data from the CJB to the replacement instrument cluster. Vehicle coding data such as engine type and market is retrieved and used to update the replacement instrument cluster.
The car configuration file will also need to be updated using the Land Rover approved diagnostic system if the vehicle is modified in service from its original factory specification. This can include fitting non-standard wheels and/or tires, or optional accessory dealer fit components with an electrical interface.