Land Rover Discovery: Electronic Engine Controls
- Ingenium i4 2.0l Diesel
/ Description
ENGINE CONTROL MODULE (ECM)
![ENGINE CONTROL MODULE (ECM)](images/books/227/index462(4).jpg)
The ECM is located behind the secondary bulkhead panel in the centerline
of the vehicle. The ECM is attached to a bracket with four screws which is
secured to the bulkhead panel. The ECM receives inputs from various
sensors and outputs reference voltages and signal information to other
sensors for engine control.
The ECM receives and processes information from the following input
sources:
- Crankshaft Position (CKP) sensor
- Camshaft Position (CMP) sensor
- Brake pedal switch
- Glow plug control module
- Ambient Air Temperature (AAT) sensor
- Engine cooling fan control module
- Fuel Pump Driver Module (FPDM)
- If the vehicle is equipped with manual transmission:
- Clutch pedal position sensor
- Clutch Bottom Of Travel (BOT) switch
- Diesel Exhaust Fluid (DEF) tank module
- DEF heater control unit
- Post Selective Catalyst Reduction (SCR) nitrogen oxide (NOx) sensor
module
- Transmission Control Switch (TCS) - Automatic transmission only
- Engine Coolant Temperature (ECT) sensor - electric thermostat housing
- ECT sensor - Radiator outlet
- Heated Oxygen Sensor (HO2S)
- Water In Fuel (WIF) sensor
- Fuel rail Pressure Control Valve (PCV)
- Fuel Rail Pressure (FRP) sensor
- Fuel temperature sensor
- Mass Air Flow and Temperature (MAFT) sensor
- Electric throttle
- Cylinder head temperature sensor
- Cylinder block temperature sensor
- Oil pressure and temperature sensor
- Variable coolant pump - shroud position
- Variable Geometry Turbocharger (VGT) vane actuator
- Pre-catalyst exhaust gas temperature sensor
- Manifold Absolute Pressure and Temperature (MAPT) sensor
- Exhaust Gas Recirculation (EGR) valve - High Pressure (HP)
- Charge air temperature sensor (EGR cooler outlet)
- Oil pressure control solenoid
- Exhaust gas temperature sensor - post catalytic converter
- EGR pressure sensor - Low Pressure (LP) EGR
- Brake vacuum sensor.
Outputs:
- Heated Oxygen Sensor (HO2S)
- Variable Camshaft Timing (VCT) solenoid
- Fuel injector (4 off)
- Variable coolant pump - shroud solenoid control
- Variable Geometry Turbine (VGT) vane actuator
- HP Exhaust Gas Recirculation (EGR) valve
- LP EGR valve
- Fuel metering valve
- Fuel rail Pressure Control Valve (PCV)
- Electric thermostat
- Glow plug control module
- Accelerator Pedal Position (APP) sensor
- Fuel Pump Driver Module (FPDM)
- Diesel Exhaust Fluid (DEF) tank module
- DEF heater control unit
- Transmission Control Module (TCM) - Automatic transmission only
- Electric throttle
- Engine cooling fan control module.
The ECM is connected to the vehicle harnesses via two connectors. The
ECM contains data processors and memory microchips. The output signals
to the actuators and sensors are in the form of ground paths provided by
driver circuits within the ECM. The ECM driver circuits produce heat during
normal operation and dissipate this heat via the ribbed casing.
The ECM performs self-diagnostic routines and stores fault codes in its
memory. These fault codes and diagnostics can be accessed using the
approved diagnostic system. If the ECM is to be replaced, the new ECM is
supplied 'blank' and must be configured to the vehicle using an approved
diagnostic system. A 'flash' electrically erasable programmable read only
memory allows the ECM to be externally configured, using an approved
diagnostic system, with market specific or new tune information up to 14
times. If a fifteenth update is required the ECM must be replaced. The
current engine tune data can be accessed and read using an approved
diagnostic system.
When a new ECM is equipped, it must be synchronized to the Central
Junction Box (CJB) and the Electric Steering Column Lock (ESCL) control
module for immobilization purposes using an approved diagnostic system.
ECM's cannot be 'swapped' between vehicles.
The ECM is connected to the engine sensors which allow it to monitor the
engine operating conditions. The ECM processes these signals and
determines the actions necessary to maintain optimum engine performance
in terms of driveability, fuel efficiency and exhaust emissions. The memory
of the ECM is programmed with instructions for how to control the engine,
this known as the strategy. The memory also contains data in the form of
maps which the ECM uses as a basis for fueling and emission control. By
comparing the information from the sensors to the data in the maps, the
ECM is able to calculate the various output requirements. The ECM contains
an adaptive strategy which updates the system when components vary due
to production tolerances or ageing.
Some sensors receive a regulated voltage supplied by the ECM. This avoids
incorrect signals caused by voltage drop during cranking.
The ECM receives a vehicle speed signal on the High Speed Controller Area
Network (HS-CAN) powertrain systems bus from the Anti-lock Brake System
(ABS) control module. Vehicle speed is an important input to the ECM
strategies. The ABS control module derives the speed signal from the ABS
wheel speed sensors. The frequency of this signal changes according to
road speed. The ECM uses this signal to determine the following:
- When to permit speed control operation
- To control the operation of the speed control system
- Implementation of the idle strategy when the vehicle is stationary.
READ NEXT:
The CKP sensor is located at the front left side of the engine. The sensor is
located in a hole in the lower timing chain cover and is secured with a screw.
The sensor receives a 5V reference volta
The electric throttle is located between the charge cooler connecting pipe
and the intake manifold. The electric throttle is secured to the manifold with
four Torx head bolts.
The electric throttle
The fuel rail Pressure Control Valve (PCV) is located in a threaded port in
the
rearward end of the fuel rail. The PCV regulates the fuel pressure within the
fuel rail and is controlled by the ECM
SEE MORE:
CAUTION:
Never improvise lifting tackle.
There is always a danger when loads are lifted or suspended. Never work
under an unsupported, suspended or raised load, for example a suspended
engine.
Always make sure that lifting equipment such as jacks, hoists, axle stands
and slings are adequate and sui
Do not ignore warning lamps or
indicators. Take appropriate
action as soon as possible. Failure
to do so may result in death or
serious injury, or serious damage
to the vehicle.
RED warning lamps are for primary
warnings. A primary warning must be
investigated immediately by the driver or
qualified