sensor JAGUAR XF 2009 1.G AJ133 5.0L Engine Manual

Technical TrainingNP10-V8JLR: AJ133 5.0-Liter DFI V8 Engine04/14/20093-29
Engine Management SystemViscous Fan Control
VISCOUS FAN CONTROL (LAND ROVER ONLY)
On Land Rover vehicles, the ECM uses an electroni-
cally-controlled viscous-coupled fan to provide engine
cooling. The ECM supplies the fan with a PWM signal
that controls the amount of slippage of the fan, thus pro-
viding the correct amount of cooling fan speed and air-
flow. The EMS uses a Hall-effect sensor to determine the
fan speed.
Failure Modes
• Solenoid drive open circuit
• Short circuit to battery voltage or ground
• Fan speed monitor open circuit
• Physically damaged fan or viscous coupling

3-3004/14/2009NP10-V8JLR: AJ133 5.0-Liter DFI V8 EngineTechnical Training
Controller Area Network Engine Management System
CONTROLLER AREA NETWORK
The Controller Area Network (CAN) is a high-speed
serial interface for sharing dynamic signals between elec-
tronic control modules. CAN communications are ‘self-
checked’ for errors, and if an error is detected the message
is ignored by the receiving electronic control module.
Due to the high rate of information exchange, the system
has a high degree of latency. This allows for a high num-
ber of errors to be present without reducing the data
transfer rate. In practice, this is a very reliable system.
Each CAN message is transmitted by one electronic con-
trol module and received by all other electronic control
modules on the CAN bus. Each message contains a fixed
structure of signals. The data exchanged is used so that
each electronic control module does not need to have a
hardwired sensor for each input. The CAN message iden-
tifiers are arranged by a network tool, which can guarantee
that all messages meet their specified timing needs.
Signal Overview
The CAN communication system is a differential bus
using a twisted pair that is normally very reliable. If either
or both of the wires of the twisted pair CAN bus is open-
or short-circuited, a CAN time-out fault will occur.
Below is a list of additional electronic control modules that
the ECM will communicate with on the CAN network:
• Instrument cluster
• Steering angle sensor
•TCM
• Active rear locking differential, if equipped
• Adaptive cruise control
• Electronic parking brake
Failure Modes
• CAN bus wiring short circuit or open circuit
• Incompatible software and message versions