DDEC TROUBLESHOOTING
ABSTRACT
This manual provides instruction for troubleshooting the Detroit Diesel Electronic Controlled
(DDEC®) engines, with two or three (multiple) ECMs.
Specifically covered in this manual are troubleshooting and repair steps that apply to the DDEC
III and DDEC IV systems.
To reduce the chance of personal injury and/or property
damage, the following instructions must be carefully
observed. Proper service and repair are important to
the safety of the service technician and the safe, reliable
operation of the engine. If part replacement is necessary, the
part must be replaced with one of the same part number or
with an equivalent part number. Do not use a replacement
part of lesser quality. The service procedures recommended
and described in this manual are effective methods of
performing repair. Some of these procedures require the
use of specially designed tools. Accordingly, anyone who
intends to use a replacement part, procedure or tool which
is not recommended, must first determine that neither
personal safety nor the safe operation of the engine will
be jeopardized by the replacement part, procedure or tool
selected. It is important to note that this manual contains
various "Cautions" and "Notices" that must be carefully
observed in order to reduce the risk of personal injury
during repair, or the possibility that improper repair may
damage the engine or render it unsafe. It is also important
to understand that these "Cautions" and "Notices" are not
exhaustive, because it is impossible to warn personnel of
the possible hazardous consequences that might result
from failure to follow these instructions.
All information subject to change without notice.
6SE497 9709 Copyright © 1997 DETROIT DIESEL CORPORATION
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