LAND ROVER V8
43
DESCRIPTION AND OPERATION
Should a malfunction of the component occur the
following fault codes may be evident and can be
retrieved by Testbook:
•
P0340 - (Signal open & short circuit to vehicle
supply or ground).
The fault condition has to be detected for more than
100 cam pulses (25 revolutions) when the engine
speed is greater than 500 rev/min.
NOTE: It is physically possible to
interchange the camshaft gear wheel fitted
to pre-99MY and post-99MY vehicles.
However, because the GEMS and Motronic
systems are incompatible, an incorrect camshaft
signal will be received by the ECM and a P0340
fault code will result.
Mass Air Flow (MAF) and Intake Air Temperature
(IAT) sensor - (from 99MY)
The MAF/IAT sensor is located at the RHS of the
engine compartment, in the air intake duct between
the air filter housing and the inlet manifold. The
complete assembly forms part of the air intake tube,
but the sensor itself is attached by two torx screws
and can be removed from the intake tube if
necessary.
The upper section of the intake tube containing the
MAF/IAT sensor is embossed with an arrow indicating
the direction of air flow, always ensure the unit is fitted
in the correct orientation.
CAUTION: Take care handling the sensor
unit, it should not be dropped or roughly
handled, ensure that the unit remains free
of contamination.
The sensor has a five pin connector which connects to
the ECM via the engine harness. The connector has
silver plated terminals for low current signals and
corrosion protection. The harness is clipped to prevent
vibration of the terminals.
MAF SENSOR
The Mass Air Flow sensor utilises a "hot film" element
contained in the air intake tube to monitor the mass
flow of the air stream being drawn into the engine.
The MAF sensor contains two sensing elements, one
element is controlled at ambient temperature (e.g.
25
°
C (77
°
F), while the other is heated to 200
°
C
(360
°
F) above the ambient temperature (e.g. 225
°
C
(437
°
F)).