Detroit Diesel MBE 900 User manual

ATTENTION
The information in this document is accurate as of May 2005 and is subject to change
without notice. This manual is to be used in conjunction with the MBE Electronic Controls
Troubleshooting Guide, 6SE422.
Detroit Diesel®,DDC
®,DDEC ®and the spinning arrows design are registered trademarks of
Detroit Diesel Corporation. Diagnostic Link®is a registered trademark of the Detroit Diesel
Corporation.

PRELIMINARY MBE EGR TECHNICIAN'S GUIDE
TABLE OF CONTENTS
1 INTRODUCTION ................................................................................................................. 1-1
1.1 VEHICLE INSPECTION .................................................................................................. 1-2
1.2 OPERATOR INFORMATION ........................................................................................... 1-3
1.3 TROUBLESHOOTING TIPS ........................................................................................... 1-4
1.3.1 LOW POWER ............................................................................................................. 1-4
1.3.2 FUEL SYSTEM ........................................................................................................... 1-5
1.3.3 AIR SYSTEM .............................................................................................................. 1-5
1.3.4 CHASSIS DYNAMOMETER TESTING ...................................................................... 1-6
1.3.5 EXHAUST SMOKE ..................................................................................................... 1-7
1.3.6 COOLANT LOSS ........................................................................................................ 1-9
1.3.7 INTERMITTENT ISSUES ........................................................................................... 1-9
2COMPONENTS................................................................................................................... 2-1
2.1 MBE 4000 ENGINES WITH EGR SYSTEMS ................................................................. 2-5
2.1.1 TURBOCHARGER AND EXHAUST MANIFOLD ....................................................... 2-9
2.1.2 EXHAUST GAS RECIRCULATION SYSTEM ............................................................. 2-10
2.2 MBE 900 ENGINES WITH EGR SYSTEMS ................................................................... 2-15
2.2.1 TURBOCHARGER AND EXHAUST MANIFOLD ....................................................... 2-20
2.2.2 EXHAUST GAS RECIRCULATION SYSTEM ............................................................ 2-22
3 EGR OPERATION ............................................................................................................... 3-1
4CODES................................................................................................................................4-1
4.1 DIAGNOSTIC TROUBLESHOOTING ............................................................................. 4-1
4.1.1 SHUTDOWN-ENGINE PROTECTION FAULT CODE = RED ..................................... 4-1
4.1.2 DERATE-ENGINE PROTECTION FAULT CODE = BLUE .......................................... 4-1
4.1.3 PERFORMANCE FAULT CODES = YELLOW ........................................................... 4-1
4.2 CODE DESCRIPTIONS .................................................................................................. 4-2
4.3 TROUBLESHOOTING OF PERFORMANCE CODES .................................................. 4-8
4.3.1 DESCRIPTION OF SID 146 ...................................................................................... 4-9
4.3.2 TROUBLESHOOTING SID 146 .................................................................................. 4-10
4.3.2.1 146/0 — EGR TEMPERATURE ABOVE NORMAL .............................................. 4-11
4.3.2.2 146/1 — EGR TEMPERATURE BELOW NORMAL ............................................. 4-13
4.3.2.3 146/2 — ERRATIC DATA ...................................................................................... 4-15
4.3.2.4 146/7 — EGR VALVE NOT RESPONDING ......................................................... 4-17
4.3.2.5 146/12 — BAD COMPONENT ............................................................................. 4-19
4.3.2.6 VERIFYING REPAIRS .......................................................................................... 4-20
4.4 ENGINE PROTECTION .................................................................................................. 4-21
5TESTING............................................................................................................................. 5-1
6 DETROIT DIESEL DIAGNOSTIC LINK/SNAPSHOTS ...................................................... 6-1
6.1 WORKING WITH DDDL SNAPSHOTS ........................................................................... 6-1
6.2 USING SNAPSHOT REPLAY CONTROLS .................................................................... 6-5
6.3 E-MAILING SNAPSHOT FILES ..................................................................................... 6-11
All information subject to change without notice. (Rev. 5/05) i
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TABLE OF CONTENTS PRELIMINARY
7 SNAPSHOT EXAMPLES .................................................................................................... 7-1
7.1 NORMAL ENGINE OPERATION SNAPSHOTS ............................................................. 7-2
7.1.1 COLD ENGINE AT IDLE ............................................................................................. 7-2
7.1.2 WARM ENGINE WITH NO LOAD .............................................................................. 7-4
7.1.3 MBE 4000 ENGINE AT VARIABLE SPEEDS AND LOADS ....................................... 7-6
7.1.4 MBE 900 ENGINE AT VARIABLE SPEEDS AND LOADS ......................................... 7-7
7.2 PROBLEM ENGINE OPERATION SNAPSHOTS ........................................................... 7-8
7.2.1 ENGINE WITH NO EGR TEMPERATURE READING ............................................... 7-8
7.2.2 ENGINE WITH ABOVE NORMAL EGR TEMPERATURE READINGS ...................... 7-10
APPENDIX A: LIST OF ACRONYMS ........................................................................................... A-1
APPENDIX B: MBE DDEC WIRING SCHEMATICS ..................................................................... B-1
APPENDIX C: SERVICE INFORMATION LETTERS ................................................................... C-1
ii All information subject to change without notice. (Rev. 5/05)
7SE940 0505 Copyright © 2005 DETROIT DIESEL CORPORATION

PRELIMINARY MBE EGR TECHNICIAN'S GUIDE
1INTRODUCTION
The MBE EGR Technician's Guide was created to provide qualified service technicians with a
detailed explanation of the Exhaust Gas Recirculation (EGR) system to facilitate quicker and
more effective diagnosing of MBE EGR related issues.
Prerequisites for effective diagnosis include the following topics:
Familiarity with the DDC computer software associated with DDC products
Knowledge of both the engine and principles of vehicle operation
Ability to perform and understand service manual and troubleshooting manual procedures
Availability of and the training to use gages and diagnostic test equipment
The most essential tool to properly diagnose and troubleshoot an MBE EGR engine is the Detroit
Diesel Diagnostic Link®(DDDL). This tool will provide all the help needed as it contains proper
troubleshooting information for all products.
NOTE:
It is absolutely critical that you understand the EGR system to be qualified to offer any
type of proper diagnostics. Do not waste time trying to troubleshoot a DDC product you
are not qualified to troubleshoot. Your company may incur wasted labor hours. If you are
qualified to perform a troubleshooting task and have spent more than one hour on that
task, STOP, and contact the Detroit Diesel Customer Support Center at 313-592-5800.
Once you have discussed your options with a technical support person, you can perform
the required tests and evaluations. Please keep in contact with your technical support
person. This allows you to stay on track.
All information subject to change without notice. (Rev. 5/05) 1-1
7SE940 0505 Copyright © 2005 DETROIT DIESEL CORPORATION

INTRODUCTION PRELIMINARY
1.1 VEHICLE INSPECTION
Check the following concerns prior to starting any troubleshooting:
Ensure engine serial number on the DDEC Engine Control Unit (DDEC-ECU) matches
the engine serial number.
Walk around the vehicle and look for obvious problems such as leaks (air or liquid).
Check the fuel filters to ensure they are secure and tight.
NOTE:
The MBE 4000 has a water separator and a fuel filter. The MBE 900 has aprefilter
and main filter.
Check for a restricted air filter.
Inspect truck frontal area for airflow restriction through the Charge Air Cooler (CAC)
and radiator.
Ensure that the fuel tank level is at least 1/4 full.
Look for any vehicle damage that could affect vehicle performance or fuel economy.
Investigate any prior repairs that could affect vehicle performance.
Check for damaged mating of the connector halves or terminals not fully seated in the
connector body (backed out terminals).
Look for improperly formed or damaged terminals. Carefully inspect all connector
terminals in the suspect circuit to determine proper contact tension. Use a mating terminal
to test the contact tension.
Check for electrical system interference causedbyadefectiverelay,DDEC-ECUdriven
solenoid, or a switch causing an electrical surge. Look for concerns with the charging
system (alternator, etc.). In certain cases, the concern can be made to occur when the faulty
component is operated as in the case of a relay.
Verify that alternator and battery grounds are clean and making good contact.
Wiggle wires and harnesses to try to make the concern active, or reoccur.
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PRELIMINARY MBE EGR TECHNICIAN'S GUIDE
1.2 OPERATOR INFORMATION
This section should serve as a guideline for the technician. Talk to the operator/driver. Be specific!
DRIVER QUESTIONNAIRE
Ask the driver to answer the following questions before attempting to repair an intermittent
concern, or a concern with symptoms but no diagnostic codes. Use their responses to these
general questions as a guideline:
1. How often does the concern occur? (Can the driver operate the vehicle and demonstrate
the concern to you in less than 30 minutes? If the concern is repeatable, take the vehicle
for a drive with the Detroit Diesel Diagnostic Link (DDDL) connected. Start the snapshot
at the beginning of the road test, use the mark user event space to track problems, and
end the snapshot at the conclusion of the road test. Ensure you can operate the vehicle
after correcting the concern without duplicating the symptoms at the operating conditions
before releasing the unit to verify the concern is corrected.)
2. Has the vehicle been to other shops for the same concern? (If so, call the other shops
and find out what has been done. Avoid replacing the same components again unless
absolutely sure they are the source of the concern. It is unlikely the same component will
fail again following a recent replacement.)
3. Did the radio, dash gages, or lights momentarily turn OFF when the concern occurred?
(If other vehicle devices are affected, this indicates there may be something wrong with
the ignition wiring.)
4. Does the concern occur only at specific operating conditions? (Operate the engine under
similar load conditions.)
5. Does the concern occur at a specific engine operating temperature? (Operate the engine
at this temperature while attempting to duplicate the concern. Use the snapshot feature
on the DDDL.)
6. Does the concern occur at a specific engine operating altitude? (If possible, troubleshoot
the concern at this altitude.)
7. Does the concern occur only when above or below specific outside temperatures? (If
possible, troubleshoot the concern in this temperature range.)
8. Does the concern occur during other conditions, e.g. during or after rain, spray washing,
or snow? (If so, thoroughly inspect the connectors for moisture entry.)
9. Did the concern occur at a specific vehicle speed? (If the problem occurs at a specific
vehicle speed, check the parameters affecting vehicle speed to verify they are programmed
close to the vehicle speed where the problem occurs. Check Vehicle Speed and watch
the DDDL {snapshot} for changes to see if the pulse wheel [Vehicle Speed Sensor
{VSS} signal] is loose.)
10. Does the concern occur at a specific engine rpm? (If the concern occurs at a specific
engine rpm, unplug the oil, coolant, and air temperature sensors, and note any changes to
the concern. Gather this data and contact the Detroit Diesel Customer Support Center
at 313-592-5800.)
All information subject to change without notice. (Rev. 5/05) 1-3
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INTRODUCTION PRELIMINARY
1.3 TROUBLESHOOTING TIPS
This section provides tips on troubleshooting complaints of low power, excessive oil consumption,
exhaust smoke, coolant loss, and intermittent concerns. The following lists of questions are only
guidelines. The service outlet need not consider every question to resolve the complaint. The
questions to consider should depend upon the circumstances surrounding the vehicle symptoms.
The technician should ask the operator questions for these seven basic concerns. They are
Low Power, Fuel System, Air System, Oil Consumption, Exhaust Smoke, Coolant Loss, and
Intermittent Concerns.
1.3.1 LOW POWER
The basic questions to check for Low Power are:
What caused you to suspect low power?
When did the low power concern start?
Are you aware of any diagnostic or performance codes?
Are you running an unusually heavy load?
Has the engine been serviced recently? (If yes and the concern occurred after servicing,
the servicing outlet should be involved.)
Is the air filter clean? (Verify that inlet air is not restricted.)
Are the fuel filter and water separator clean? (A plugged filter will restrict fuel flow
and result in low power.)
How many miles are on the unit? (If mileage is high [several hundred thousand miles],
valve lash may need adjusting or nozzles may need replacement.)
Is the unit hard starting? (If there is a hard starting issue, there may be a fuel system
related concern or low compression.)
Are the vehicle fuel tanks vents are open? (Make sure the vents are open. Plugged vents
will create a vacuum in the fuel tanks as fuel is consumed and result in a gradual power
loss as the vehicle is operated.)
Is there a misfire at idle or at no-load speed? (If yes, there may be a fuel or mechanical
system concern.)
Has there been a history of low power complaints? (Check warranty claim status and
prior Remedy tickets.)
Is there evidence of white, black, or blue exhaust smoke? (If yes, see smoke
troubleshooting guide.)
Is the fuel level in the fuel tank low? (If below 1/4 tank, it may result in high fuel
temperature above 80 C (176 F). High fuel temp can also cause low power.)
Is the exhaust flap fully open and are the exhaust system restrictions eliminated?
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PRELIMINARY MBE EGR TECHNICIAN'S GUIDE
Are there any active or historic codes? (Record ALL codes in bold.)
NOTE:
If a printer is not available, record all codes with the repair order as they may be required
at a later review.
Is the boost pressure normal? (See engine performance curve specification.)
Are the camshaft and crankshaft sensors installed correctly?
Is the valve lash correct? (Verify!)
Is the battery holding power? (Verify voltage is correct. Low voltage will result in
multiple codes.)
Is there a misfire at idle or no load speed? (If yes, run a fuel system inspection according
to the procedure listed in the service manual.)
For MBE 4000 engines with turbo brake, is the wastegate operating properly? (See Service
Information Letter No. 03 TS-51.)
When the accelerator pedal is in the full throttle position, does the DDDL or minidiag2
sense 100 % throttle?
1.3.2 FUEL SYSTEM
The basic questions to ask for the Fuel System are:
Are the correct fuel filter and water separator installed and clean?
Is the Fuel System in proper working order? (Inspect the Fuel System. Refer to MBE 4000
Service Manual, 6SE412 and MBE 900 Service Manual, 6SE414.)
Are the overflow valve and fuel pump operating properly?
Is the vehicle using fuel with the required specific gravity? (API 34-38 is required for
No. 2 diesel fuel.)
Inspect the water separator for clogging.
1.3.3 AIR SYSTEM
Inspect the Air System as follows:
Check air dryer for system leaks.
Check for leaks at all hose clamp locations, and charge air cooler.
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INTRODUCTION PRELIMINARY
PRESSURIZED AIR AND FLYING PARTICLES
To avoid injury to eye or face, wear a face shield or goggles
when conducting a pressure test.
NOTICE:
Use proper tools for pressure testing Charge Air Cooler system.
Tools not rated for adequate pressure or with improper connections
can break free and cause engine damage.
Pressure check the air inlet system with 172 kPa (25 psi) regulated shop air. Use liquid
soap to identify any leaks. Pressure check from turbo discharge connection to cylinder
head noting and correcting leaks at hose clamps and on hoses or air-to-air charge cooler.
NOTE:
If air-to-air charge cooler is leaking from this initial check, pressure check it separately
at 207 kPa (30 psi). Pressure must not lose more than 35 kPa (5 psi) in 15 seconds
with shop air off.
Verify turbocharger is functioning properly.
1.3.4 CHASSIS DYNAMOMETER TESTING
Run the vehicle on a chassis dynamometer and look at the following:
EXHAUST FUMES
To avoid injury or injury to bystanders from fumes, engine or
vehicle fuel system service operations should be performed
in a well ventilated area.
NOTE:
Ram air fans in front of vehicles and room ventilation are required.
Record the following data at 1650, 1500, and 1350 rpm, (Direct drive):
Wheel horsepower with vehicle fan on (Wheel horsepower above 80 % of rated power
at the wheels is acceptable. Refer to performance curve.)
Intake Manifold Pressure (If reading is erratic, take a snapshot.)
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PRELIMINARY MBE EGR TECHNICIAN'S GUIDE
Fuel Temperature and Pressure (If data is erratic, take a snapshot.)
NOTE:
Record vehicle specifications in the event there is a need to predict vehicle performance
using Spec Manager.
Record crankcase pressure at high idle. DDC maximum specifications are:
For the MBE 4000 engines, the maximum is 0.37 kPa (1.5 in. H2O) for non-EGR
engines (1998) and 2.0 kPa (8.0 in. H2O) for EGR engines (2004).
For the MBE 900 engine, the maximum is 0.37 kPa (2.5 in. H2O) for both non-EGR
engines (1998) and EGR engines (2004).
1.3.5 EXHAUST SMOKE
The basic questions to ask for Black Exhaust Smoke are:
NOTE:
Black Smoke is soot from partially oxidized (burned) fuel at high temperatures.
Is the air filter restricted? (Reduced air flow = lack of oxygen, incomplete/high temperature
combustion and soot)
Are exhaust brake devices functioning properly? (Reduced air flow = incomplete
combustion and soot)
Is the CAC cracked? (Reduced air flow = incomplete combustion and soot)
Are the intake air manifold gasket(s) leaking? (Reduced air flow = incomplete combustion
and soot)
NOTE:
The MBE 4000 uses multiple air manifold gaskets to cover individual cylinder heads. The
MBE 900 uses one gasket for every two adjacent cylinders on a single cylinder head.
Are there air bubbles in the coolant? (Head gasket failure = vaporized water in exhaust)
Are there air bubbles in the fuel? (Fuel line/pump leak = late fuel injection = raw
vaporized fuel in exhaust)
Are the valve clearances correct? (Incorrect valve timing = incorrect combustion timing
and soot)
Is the comparative cylinder compression test result correct/within specifications? (Low
compression = incomplete/poor combustion)
Has a fuel nozzle failed causing excess fuel delivery? (Excess fuel = incomplete
combustion and soot)
Is the EGR valve stuck open? (Excess exhaust gas recirculation = insufficient oxygen,
incomplete combustion, and soot)
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INTRODUCTION PRELIMINARY
Is the Intake Manifold Pressure (IMP) Sensor/Turbocharger Boost Sensor (TBS) working
correctly?
The basic questions to ask for Blue Exhaust Smoke are:
NOTE:
Blue Smoke is partially burned lubrication oil that ends up as a raw vaporized oil in the
exhaust soot from partially oxidized (burned) fuel at high temperatures.
Is the comparative cylinder compression test result correct/within specifications? (Low
compression = incomplete/poor combustion)
Is the oil level above the maximum level? (Excess oil = poor combustion and raw
vaporized oil in the exhaust)
Does the oil quality meet the recommended specification? (Poor quality oil = piston
ring wear and poor combustion)
Is the turbocharger leaking oil into the exhaust? (Oil in exhaust = poor combustion)
Are the valve stem seals functioning? (Oil leaking past seal = poor combustion)
The basic questions to ask for White Exhaust Smoke are:
NOTE:
White Smoke is usually partially burned fuel that ends up as raw vaporized fuel in the
exhaust. White Smoke can also be the result of a coolant leak that ends up as steam
in the exhaust.
Is the fuel quality within DDC specification? (Cetane No. minimum: 45, Cetane Index,
minimum: 40)
Is the air preheater installed and functioning properly? (Cold air = raw vaporized fuel
in the exhaust)
Are there air bubbles in the coolant? (Suggests a head gasket failure = vaporized water in
exhaust)
Are there air bubbles in the fuel? (Suggests a fuel line/pump leak = late fuel injection =
raw vaporized fuel in exhaust)
Are the valve clearances correct? (Incorrect valve timing = incorrect combustion timing)
Is the charge air cooler cracked? (Reduced air flow = incomplete combustion and soot)
NOTE:
Refer to Service Information Letter 05 TS-01 for service information on cracked charge
air coolers. See Figure C-16 and Figure C-17.
Is the comparative cylinder compression test result correct/within specifications? (Low
compression = incomplete/poor combustion)
Has a fuel nozzle failed causing excess fuel delivery? (Excess fuel = incomplete
combustion and raw fuel in exhaust)
1-8 All information subject to change without notice. (Rev. 5/05)
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PRELIMINARY MBE EGR TECHNICIAN'S GUIDE
Is the IMP Sensor/TBS working correctly?
1.3.6 COOLANT LOSS
The basic questions to ask for Coolant Loss are:
Has the oil level risen? (If so, it would suggest coolant in the oil and a head gasket failure.)
Have you noticed any coolant leaks or coolant puddles under the vehicle?
How often do you add coolant?
Is the radiator cap on tight and sealing properly?
What type of coolant is being used?
What type of inhibitor is being used?
1.3.7 INTERMITTENT ISSUES
The basic questions to ask with Intermittent Concerns are:
When was the last time the intermittent concern occurred?
Does the Amber Warning Lamp (AWL) come on?
Does the concern only occur in damp or rainy conditions?
Does the concern occur when the vehicle hits a bump or rough road?
Does the engine miss, drop to idle, quit running, or exhibit hard starting?
Is there any pattern related to trip miles or engine temperature?
All information subject to change without notice. (Rev. 5/05) 1-9
7SE940 0505 Copyright © 2005 DETROIT DIESEL CORPORATION

INTRODUCTION PRELIMINARY
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1-10 All information subject to change without notice. (Rev. 5/05)
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PRELIMINARY MBE EGR TECHNICIAN'S GUIDE
2COMPONENTS
The purpose of the Exhaust Gas Recirculation (EGR) System is to reduce engine emissions in
accordance with Environmental Protection Agency (EPA) regulations.
The key components of an MBE EGR system consists of:
EGR Valves
EGR Cooler
Reed Valves
EGR Mixer
All information subject to change without notice. (Rev. 5/05) 2-1
7SE940 0505 Copyright © 2005 DETROIT DIESEL CORPORATION

COMPONENTS PRELIMINARY
The MBE engines for NAFTA On-Highway 2004 applications use a liquid-cooled EGR system.
Exhaust is routed from the exhaust manifold, through the EGR shutoff valve (MBE 4000 only), the
EGR cooler, the EGR control valve, the reed valves (all except the MBE 906), and the EGR mixer
in the intake manifold where they are mixed with the charge air. To view the arrangement of these
components, see Figure 2-1 for the MBE 4000 engine and Figure 2-2 for the MBE 900 engine.
Figure 2-1 Schematic of MBE 4000 EGR System
2-2 All information subject to change without notice. (Rev. 5/05)
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PRELIMINARY MBE EGR TECHNICIAN'S GUIDE
Figure 2-2 Schematic of MBE 900 EGR System
All information subject to change without notice. (Rev. 5/05) 2-3
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COMPONENTS PRELIMINARY
The addition of cooled exhaust gas back into the combustion airflow reduces the peak in
cylinder combustion temperature. The formation of Oxides of Nitrogen (NOx) is lessatlower
combustion temperatures.
Reed valves are employed on all MBE engines except for model 906. In order to drive exhaust
gas into the charge air, the pressure in the exhaust manifold must be higher than the pressure in
the intake manifold. The pressure in the exhaust manifold changes over time, peaking when
exhaust valves open. Exhaust passes through the reed valves during these pressure peaks. The
reed valves permit transport of exhaust only during the time when the exhaust pressure is greater
than the charge air pressure.
The EGR systems for the MBE 900 and MBE 4000 engines are similar but differ in their specific
components. The EGR components are listed in Table 2-1.
Component MBE 904/924 MBE 906 MBE 926 MBE 4000
Asymmetrical
Turbocharger *Yes Yes Yes
EGR Valve Yes Yes Yes Yes
Shutoff Valve ———Yes
Temperature Sensor Yes Yes Yes Yes
Reed Valves Yes —Yes Yes
EGR Mixer Yes Yes Yes Yes
* Single-Flute Turbine Housing
Table 2-1 EGR Components Featured on the MBE Engines
2-4 All information subject to change without notice. (Rev. 5/05)
7SE940 0505 Copyright © 2005 DETROIT DIESEL CORPORATION