MAPT JAGUAR XFR 2010 1.G User Guide

DIAGNOSTICS

The ECM stores each fault as a DTC (diagnostic trouble code). The DTC and associated environmental and freeze frame data can be read using Jaguar approved diagnostic equipment, which can also read real time data from each sensor, the adaption
values currently being employed and the current fueling, ignition and idle speed settings.



ENGINE CONTROL MODULE Component Description



The ECM is installed in the front passenger side of the engine compartment, on a bracket attached to the engine bulkhead. The ECM has the capability of adapting its fuel and ignition control outputs in response to several sensor inputs. The ECM receives inputs from the following:
CKP sensor. CMP (camshaft position) sensors (4 off).
ECT (engine coolant temperature) sensor.
Knock sensors (4 off).
MAP (manifold absolute pressure) sensor.
MAFT sensors (2 off). MAPT (manifold absolute pressure and temperature) sensor.
Throttle position sensor.
Heated oxygen sensors (4 off).
APP sensor. Ambient air temperature sensor.
FRP (fuel rail pressure) sensor. For additional information, refer to 303-04G Fuel Charging and Controls.
Engine cooling fan. For additional information, refer to 303-03D Engine Cooling.
Stoplamp switch. For additional information, refer to 206-09 Anti-Lock Control - Stability Assist.
Speed control cancel/suspend switch. For additional information, refer to 310-03D Speed Control.
Oil level and temperature sensor. For additional information, refer to 303-01F Engine.
Fuel LP (low pressure) sensor. For additional information, refer to 310-01D Fuel Tank and Lines.
Fuel pump driver module. For additional information, refer to 310-01D Fuel Tank and Lines.
The ECM provides outputs to the following: Electronic throttle.
Main relay.
Heater elements of the heated oxygen sensors (4 off).
Fuel injectors (8 off). For additional information, refer to 303-04G Fuel Charging and Controls. www.JagDocs.com

MANIFOLD ABSOLUTE PRESSURE AND TEMPERATURE SENSOR













The MAPT sensor allows the ECM to calculate the air charge density immediately before it enters the cylinders. This is used to adjust the ignition timing relative to the boost pressure, and to monitor the performance of the charge air coolers.

The MAPT sensor is installed in the rear of the LH intake manifold. The sensor is secured with a single screw and sealed with an O-ring. A four pin electrical connector provides the interface with the engine harness.

THROTTLE POSITION SENSORS

The TP (throttle position) sensors allow the ECM to determine the position and angular rate of change of the throttle blade. There are two TP sensors located in the electronic throttle. See below for details of the electronic throttle. If aTP sensor fails, the ECM:
Adopts a limp home mode where engine speed is limited to a maximum of approximately 2000 rev/min
Discontinues evaporative emissions control
Discontinues closed loop control of engine idle speed.

With a failed TP sensor, the engine will suffer from poor running and throttle response.
HEATED OXYGEN SENSORS



Item Description A Upstream heated oxygen sensor B Downstream heated oxygen sensor The heated oxygen sensors allow the ECM to measure the oxygen content of the exhaust gases, for closed loop control of the fuel:air mixture and for catalytic converter monitoring.

An upstream heated oxygen sensor is installed in the outlet of each exhaust manifold, which enables independent control of
the fuel:air mixture for each cylinder bank. A downstream heated oxygen sensor is installed in each catalytic converter, which
enables the performance of the catalytic converters to be monitored.

Oxygen sensors need to operate at high temperatures in order to function correctly. To achieve the high temperatures required,
the sensors are fitted with heater elements that are controlled by a PWM (pulse width modulation) signal from the ECM. The heater elements are operated immediately after each engine start and during low load conditions when the temperature of the
exhaust gases is insufficient to maintain the required sensor temperature. The PWM duty cycle is carefully controlled to prevent thermal shock to cold sensors. A non-functioning heater delays the sensor’s readiness for closed loop control and
increases emissions.

The upstream heated oxygen sensors produce a constant voltage, with a variable current that is proportional to the lambda
ratio. The downstream heated oxygen sensors produce an output voltage dependant on the ratio of the exhaust gas oxygen to