Mack ASET AC, Руководство по обслуживанию

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Page 40
DESCRIPTION AND OPERATION
Ambient Air Temperature Sensor — P/N
64MT2118
The sensor is mounted off-engine and supplies
temperature input to the engine electronic control
unit (EECU). Location of the sensor depends
upon chassis model. But in general, it is located
at the front of the chassis mounted either on the
front crossmember behind the bumper, on a hood
hinge, hood hinge bracket, body, spring bracket
or grille guard assembly.
Combustion Air Temperature/Humidity
Sensor
— P/N 64MT445, mounted in the air inlet
tubing between the air cleaner and the
turbocharger.
VTG Position Sensor (New) — P/N 64MT458,
mounted on top of the turbocharger VTG
actuator. It indicates the position of the vanes in
the turbine housing inlet port.
VTG Wheel-Speed Sensor (New) — P/N
64MT457, mounted in the turbocharger bearing
housing where it is used to indicate turbocharger
wheel speed.
Compressor Discharge Temperature Sensor
(New)
— P/N 64MT450A, a wide-range
fast-response type mounted in the charged-air
tubing between the turbocharger and the
CMCAC.
Boost Pressure Sensor (New) — P/N
64MT446, mounted in the EGR mixer tube.
CMCAC Outlet Temperature Sensor (New) —
P/N 64MT450A, mounted in the EGR mixer tube.
EGR Temperature and MASS Flow Sensors
(New)
— Sensor pair mounted in the upper
“cool-side” EGR tube between the EGR cooler
and the mixer tube. The pair of sensors is
calibrated specifically to the upper EGR tube and
the EGR MASS Flow System module. If
replacement is required, the entire tube assembly
with its integral sensors must be replaced along
with the MASS Flow System module attached to
the back of the EECU cooling plate. Part numbers
for the tube assembly are 206MS52 (with
J-Tech™ engine brake) or P/N 206MS51 (without
engine brake).
Atmospheric Pressure Sensor — Integral to the
EECU module.
Inlet Manifold Temperature Sensor — P/N
64MT450A, mounted at a mid-point on the inlet
manifold.
Oil Pressure Sensor — Mounted at the side of
the oil filter adapter housing.
Oil Temperature Sensor — Mounted at the side
of the oil filter adapter housing.
Coolant Temperature Sensor — Mounted at the
rear of the coolant manifold.
Engine Speed Sensor — Mounted at the left
side of the flywheel housing.
Engine Position Sensor — Mounted on the front
timing cover beneath the crankcase breather
housing.
Fan Speed Sensor — Mounted on the fan-drive
hub support.
Fuel Temperature Sensor — V-MAC III
monitors fuel temperature at the cylinder block
fuel gallery inlet. This fuel temperature data is
used by the system to adjust fuel delivery for
optimized power and to provide accurate mpg
fuel consumption information.
All of these sensors are connected via a
reconfigured engine wiring harness. The harness
incorporates three geared lock-down connectors
at the EECU. The harness is also fitted with a
new Deutsch vehicle interface connector located
on the air inlet manifold below the VTG
turbocharger position controller (Figure 36). This
connector provides the connection for the
interface between the engine control system and
the chassis.
36
Figure 36 — Deutsch Connector
1. Inlet Manifold
2. VTG Position Controller 3. Vehicle Interface
Connector
5-111.bk Page 40 Monday, July 10, 2006 2:26 PM