2003 MAN D28 Inline & D28V Marine Diesel Engine MMDS Repair Manual (P/N 51.99598−8117)

MAN Nutzfahrzeuge Aktiengesellschaft repair manual 51.99598−8117, technical status 09.2003, covers the 2003 MAN D28 in-line and D28V marine engines with EDC, plus D28V engines with mechanical governors. Its subject is the MAN Monitoring Diagnostic System (MMDS): component operation, installation, testing, and interfaces.

Text search, navigation, and wiring detail: Main text and many diagram labels are searchable; cover text and text within some screenshots are not. Embedded bookmarks navigate the technical sections. Small wiring labels require zooming. Printed pagination skips 138–142, and some contents/index references are offset.

• Sensor testing: Location views and checks for pressure, temperature, coolant level, RPM, generator charging voltage, and optional engine and gearbox monitoring sensors.

• Central diagnostic unit: Alarm identification, relay outputs, stored histories, load profiles, and safety functions for engine slowdown, shutdown, and overspeed testing.

• Serial displays and instruments: MMDS-LC and MMDS-L operation, MMDS-SD distribution, MMDS-DA converter checks, analog instrument testing, and MMDS-EP engine-room panel installation.

• CAN instrumentation: MMDS-CLC 6.3 configuration, CAN master tachometer settings, EasyLink slave connections, and CAN termination requirements.

• Commissioning and programming: Multi-engine setup equipment, temporary measuring sensors, laptop interfaces, and MMDS-LC programming for general ship alarms.

• Electrical drawings: EDC/MMDS and mechanical-governor circuit diagrams, central diagnostic-unit and MMDS-DA connections, component wiring, connector pinouts, and installation dimension drawings.

Written for readers with basic knowledge of marine engines and their electrical systems; MAN specifies authorized, qualified personnel for inspection, adjustment, and repair work.

Diagnostic and Monitoring Coverage

Sensor reference data include PT 1000 and Ni 1000 resistance tables, NiCrNi thermocouple voltage tables, and Hall-HT speed-sensor checks. Coolant-level probe tests cover both installed and removed probes.

The analog instrument tests distinguish missing D/A signals from faulty gauges, helping narrow down an incorrect indication before choosing a repair. Alarm explanations separate sensor and wiring failures from central-unit faults.

The storage description covers the last 8,000 alarms and 50 histories with engine-status snapshots before and after an event. Load-profile recording applies to EDC engines, not mechanically governed engines.

Engine Variants and Electrical Interfaces

EDC engines supply key operating values to MMDS through CAN communication; mechanically governed engines use dedicated sensors for those inputs. The D 2876 LE 401 section explains the optional 12-volt installation and MMDS-DC 12 conversion to the 24-volt monitoring supply.

The EDC diagram identifies the control-slide mechanism and needle-movement sensor for D 2876 LE 4.. engines, plus the second shutoff device for the D 2842 LE 409. Separate circuits document the EDC installation with a voltage converter and interfaces for the emergency running unit.

Display Setup and Commissioning

MMDS-LC programming covers alarm texts, NO/NC contacts, delays, and suppression logic through an RS 232 PC interface. The CLC 6.3 section distinguishes display versions 51.27721−7029 and 51.27721−7050, including their different screen selections.

Commissioning schemes show serial and CAN installations for up to three engines. The equipment list identifies wiring harness 51.25400−6056, data concentrator 51.27720−7017, and PC connecting cable 51.25449−6029.

The procedures reference MAN commissioning software 51.99585−4000 and ship-alarm programming software 51.99585−4030. Diagnostic hardware and software are not included with this PDF.

Repair Scope and Component Precautions

Coverage centers on MMDS electrical diagnosis and installation, without internal engine or gearbox overhaul procedures. MAN specifies use alongside publication 51.99598−8043, Electronically Controlled Diesel Injection in Conjunction with MAN Monitoring Diagnostic System (MMDS). Detailed throttle-lever control and emergency-running-unit instructions belong to separate publications.

Component warnings explain that reversed pressure-sensor polarity can destroy the MMDS input resistor, while supply voltage applied to MMDS-DA instrument outputs can destroy the converter. The safety section addresses electrical isolation and pressure hazards in oil and coolant circuits.

English PDF and Included Pages

One printable English PDF contains 159 pages total, including two cover pages, two unnumbered blank pages, one Notes page, and eight otherwise blank schematic reverse pages with headings. These pages are already included in the total; the referenced companion publications are not included.