Detroit Diesel Series 60 EGR Technician Manual page 12

INTRODUCTION
Questionnaire Response Guideline
The following are typical responses to the Driver Questionnaire:
To avoid injury from loss of vehicle/vessel control, the
operator of a DDEC equipped engine must not use or read
any diagnostic tool while the vehicle/vessel is moving.
1. If the problem is repeatable, take the vehicle for a drive with the DDDL connected and
note the conditions when the problem occurs. Be prepared to take snapshot data using the
DDDL. Ensure you operate the vehicle after correcting the problem and duplicate
the operating conditions before releasing the unit, to verify the problem is corrected.
2. If the vehicle has been to other shops for the same problem, call the other shops and find
out what has been done. Avoid replacing the same components again unless absolutely
sure they are the problem! It is unlikely a component will fail again following a recent
replacement.
3. If other vehicle devices are affected, this indicates there may be something wrong with
the ignition wiring.
4. Operate the engine under similar load conditions. Check the fuel system for restrictions,
primary filter, and fuel tanks for foreign objects blocking the fuel supply. Also, check the
air system. Utilize the DDDL snapshot feature.
5. Operate the engine at this temperature while attempting to duplicate the problem. Use the
snapshot feature on the DDDL.
6. If possible, troubleshoot the problem in this temperature range.
7. If the problem seems to occur during or after the engine is subjected to rain/spray washing,
thoroughly inspect the connectors for moisture entry.
8. 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 (VSS signal) is loose.
9. If the problem occurs at a specific engine rpm, unplug the oil, coolant, and air temperature
sensors, and note any changes to the problem. Gather this data and contact DDC Customer
Support Center at 313-592-5800.
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PERSONAL INJURY
7SE60 0506 Copyright © 2005 DETROIT DIESEL CORPORATION
All information subject to change without notice. (Rev. June 2005)