SERIES 60 EGR TECHNICIAN'S GUIDE
4
CODES
DIAGNOSTIC TROUBLESHOOTING
This section supports the DDEC IV fault codes recorded during EGR engine operation.
Diagnostic Trouble Codes (DTC)
Component, Logic, or Engine Protection Codes
Diagnostic trouble codes are generated in the ECM when a condition exists that prevents the
engine from operating at peak efficiency. Three primary codes exist Component, Logic, and
Engine Protection.
Sensor Codes = Yellow
A component DTC is activated when a specific component failure exists. This is most commonly
seen as a high volt or low volt code for a specific device. The failure can generally be found
within the component or wiring for that component.
Engine Protection Codes = Red
An engine protection DTC is activated when a engine operating condition exists that can cause
immediate damage to the engine and the engine should be shut down until the condition is
corrected to prevent additional damage.
Logic Codes = Blue
A logic DTC is activated when specific conditions occur within a given amount of time that the
calibration determines is not “normal”. For example: If the ECM commands the EGR valve to
open or close. The ECM monitors the EGR flow devices for confirmation that flow has begun
or ended.
All information subject to change without notice.
(Rev. April 2004)
4-1
7SE60 0404
Copyright © 2004 DETROIT DIESEL CORPORATION