Engine Diagnostics - Perkins 2506 Operation And Maintenance Manual

SEBU8313-02

Engine Diagnostics

Self-Diagnostics
The electronic control module has some self-
diagnostic ability. When an electronic problem with
an input or an output is detected, a diagnostic code is
generated. This indicates the specific problem with
the circuitry.
Diagnostic codes are also generated when an
abnormal engine operating condition is detected. For
example, a diagnostic code will be generated if the
low oil pressure alarm is activated. In this case, the
diagnostic code indicates the symptom of a problem.
This type of diagnostic code is called an event. An
event is triggered by the detection of an abnormal
engine operating condition.
A diagnostic code which represents a problem that
currently exists is called an active code.
A diagnostic code that is stored in memory is called a
logged code. Always service active codes prior to
servicing logged codes. Logged codes may include
the following categories:
• Intermittent problems
• Recorded events
• Performance history
Logged codes may not indicate that a repair is
needed. The problems may have been repaired since
the logging of the code. Logged codes may be
helpful to troubleshoot intermittent problems.
Diagnostic Lamp
The "DIAGNOSTIC" lamp is used to indicate the
existence of an active fault.
A fault diagnostic code will remain active until the
problem is repaired.
Fault Logging
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The system provides the capability of Fault Logging.
When the Electronic Control Module (ECM)
generates an active diagnostic code, the code will be
logged in the memory of the ECM. The Perkins
electronic service tool can retrieve codes that have
been logged. The codes that have been logged can
be cleared with the Perkins electronic service tool.
The codes that have been logged in the memory of
the ECM will be automatically cleared from the
memory after 100 hours. The following faults can not
be cleared from the memory of the ECM without
using a factory password: overspeed, low engine oil
pressure and high engine coolant temperature.
Engine Operation with Active
Diagnostic Codes
If a diagnostic lamp illuminates during normal engine
operation, the system has identified a situation that is
not within the specification. Use the electronic service
tool to check the active diagnostic codes.
The active diagnostic code should be investigated.
The cause of the problem should be corrected as
soon as possible. If the cause of the active diagnostic
code is repaired and there is only one active
diagnostic code, the diagnostic lamp will turn off.
Operation of the engine and performance of the
engine can be limited as a result of the active
diagnostic code that is generated. Acceleration rates
may be significantly slower and power outputs may
be automatically reduced. Refer to Troubleshooting ,
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"Troubleshooting with a Diagnostic Code" for more
information on the relationship between each active
diagnostic code and the possible effect on engine
performance.
Engine Operation with
Intermittent Diagnostic Codes
If a diagnostic lamp illuminates during normal engine
operation and the diagnostic lamp shuts OFF, an
intermittent fault may have occurred. If a fault has
occurred, the fault will be logged into the memory of
the Electronic Control Module (ECM).
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Operation Section
Engine Diagnostics
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