Volvo D13 User Manual

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Section 01: ENGINE 
PA1561 
20 
problem solving in the form of a code. The MCM 
and CPC continuously perform self diagnostic 
checks and monitor the other system 
components. Information for problem 
identification and problem solving is enhanced 
by the detection of faults, retention of fault codes 
and separation of active from inactive codes. 
The engine-mounted MCM includes control logic 
to provide overall engine management. System 
diagnostic checks are made at ignition on and 
continue throughout all engine operating modes. 
Sensors provide information to the MCM and 
CPC regarding various engine and vehicle 
performance characteristics. The information is 
used to regulate engine and vehicle 
performance, provide diagnostic information, 
and activate the engine protection system. 
The DDEC VI on-board diagnostic system 
accessories include the following: 
•  Check Engine telltale light (AWL); 
•  Stop Engine telltale light (RSL); 
•  Stop Engine Override switch (SEO); 
•  Diagnostic Data Link (DDL) connectors. 
 
The AWL is illuminated and a code is stored if 
an electronic system fault occurs. This indicates 
the problem should be diagnosed as soon as 
possible. The CPC illuminates the AWL and 
RSL and stores a malfunction code if a 
potentially engine damaging fault is detected. 
These codes can be accessed in one of four 
ways: 
 
• 
Commercially available J1587/J1939 
diagnostic tools. 
•  Detroit Diesel Diagnostic Link® (DDDL 7.0). 
• Flashing the AWL and RSL with the 
SEO/Diagnostic Request Switch. 
• Dashboard’s Message Center Display 
(MCD). 
2.8.2  Check Engine Telltale Light (AWL) 
The CPC illuminates the Check Engine telltale, 
mounted on the telltale light panel to indicate 
that a problem has been detected and that a 
code has been stored in the MCM memory.  
This light also has a 5-second bulb check when 
the ignition is first turned on.  
2.8.3  Stop Engine Warning Light (RSL) 
This light, also mounted on the telltale light 
panel, illuminates to indicate that a major engine 
problem is occurring (with the exception of a 5-
second bulb check when the ignition is first 
turned on).  
2.8.4  Stop Engine Override Switch (SEO) 
This switch, mounted on the dashboard, may be 
used to extend the 30-second delay period 
before engine shutdown when the Stop engine 
telltale light is illuminated. This switch can be 
repeatedly depressed in order to move the 
vehicle out of traffic. 
NOTE 
The stop engine override switch will be 
operative only if it has been depressed before 
the end of the 30 second delay period.
 
 
CAUTION 
The OVERRIDE switch must be used only in 
emergency cases, such as to move the 
vehicle out of traffic. Excessive use of this 
switch can cause serious damage to the 
engine. 
This switch is also used for DDEC diagnostic 
code requests. Press this switch with the engine 
at idle or off but with the ignition in the "ON" 
position and active codes will be flashed on the 
CHECK ENGINE and STOP ENGINE telltale 
lights alternately. 
2.8.5  Diagnostic Data Link (DDL) Connectors 
A connector is mounted on the L.H. footwell 
wall. Another connector is located in the rear 
electric compartment. They allow the connection 
of the Diagnostic Data Reader (DDR) to read 
the codes or to access pertinent data on the 
condition of the engine.  This enables a more 
complete analysis of any defect found in the 
DDEC system operation.  For more information, 
see Detroit Diesel Troubleshooting Guide 
#6SE492. 
2.9  READING DIAGNOSTIC CODES – 
FLASHING LIGHT METHOD: 
DDEC VI makes use of two types of codes: 
Active and inactive. The difference between the 
two types of codes is as follows: