Vehicle Control Unit; Sensor Locations - Detroit Diesel EPA04 MBE 4000 Operator's Manual

IDENTIFICATION

Vehicle Control Unit

The DDEC-VCU, see Figure
10, communicates with the other
electronic control units installed on
the vehicle over the J1587 and J1939
data link.
Figure 10 DDEC-VCU
Sets of data for specific applications
are stored in the DDEC-VCU
including idle speed, maximum
running speed, and speed limitation.
The DDEC-VCU receives data from
the following sources:
□ The operator (accelerator pedal
position, engine brake switch)
□ Other electronic control units (the
antilock brake system)
□ The DDEC-ECU (oil pressure and
coolant temperature)
From these data, instructions are
computed for controlling the engine
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DDC-SVC-MAN-0056 04/08 Copyright © 2008 DETROIT DIESEL CORPORATION
and transmitted to the DDEC-ECU via
the proprietary data link.
The DDEC-VCU controls
various systems, for example,
communications with the datalink and
the engine brake.
If the engine control system detects
a fault, the appropriate fault code is
broadcast on the datalink and can be
read using minidiag2, the Nexiq DDR
or DDDL PC software. Fault code
information may also be available on
the vehicle or equipment instrument
panel.

Sensor Locations

Use caution when handling the
sensors.
CHEMICAL BURNS
To avoid injury from chemical
burns, wear a face shield and
neoprene or PVC gloves when
handling sensor hoses.
The Engine Oil Pressure/Temperature
Sensor is located at the base of the oil
filter.
See Figure 11 for sensor locations on
the MBE 4000 engine.
All information subject to change without notice. (Rev. 04/08)