The Series 60 EGR Technician's Guide is intended to be used by a qualified service technician familiar with Detroit Diesel electronically controlled (DDEC) diesel engines and to provide a better understanding of the EGR system to improve the diagnosing of a Series 60® EGR system.
Prerequisites for effective diagnosis include the following topics:
- Knowledge of both the engine and vehicle principles of operation.
- Ability to perform and to understand service manual and troubleshooting manual procedures.
- Availability and training to use gages and diagnostic test equipment.
- Familiarization of the computer software associated with DDC products.
An essential tool to properly diagnose and troubleshoot a DDEC IV or DDEC V Series 60 EGR engine is the Detroit Diesel Diagnostic Link® (DDDL).
This tool will provide you all the help you will need as it contains proper troubleshooting information for all products.
Note: It is absolutely critical that you understand the EGR system to be qualified to offer any type of proper diagnostics. Do not waste time trying to troubleshoot a DDC product, you are not qualified to troubleshoot. Your company may incur wasted labor hours. If you are qualified to perform a troubleshooting task and have spent more than one hour on that task, STOP , and contact the Detroit Diesel Customer Support Center at 313-592-5800. Once you have discussed your options with a customer support center person, you can perform the required tests and evaluations. Please keep in contact with your customer support person. Doing so allows you to stay on track.
The following listed items should be checked prior to starting any troubleshooting:
- Ensure that the engine serial number on the ECM/ECU matches the serial number on the cylinder block.
- Walk around the vehicle. Look for obvious problems such as leaks (air or liquid).
- Inspect the ECM/ECU for worn isolators, debris or bolts lodged between ECM/ECU and cylinder block.
- Ensure the fuel supply shut-off valve is set to full on .
- Check that the fuel filter is secure and tight.
- Check for a restricted air filter.
- Inspect truck frontal area for air flow restriction through the CAC and radiator.
- Ensure that the fuel tank level is correct and that the fuel tank is full.
- Look for any vehicle damage.
- Investigate any prior repairs, if applicable.
- Check for broken wiring connectors.
- Check for poor mating of the connector halves or terminals not fully seated in the connector body (backed out terminals).
- Look for improperly formed or damaged terminals. All connector terminals in the problem circuit should be carefully inspected to determine proper contact tension. Use a mating terminal to test the contact tension.
- Check for electrical system interference caused by a defective relay, ECM/ECU driven solenoid, or a switch causing an electrical surge. Look for problems with the charging system (alternator, etc.). In certain cases, the problem can be made to occur when the faulty component is operated as in the case of a relay.
- Verify that alternator grounds are clean and making good contact. Disconnect the alternator belt to test.
- Wiggle wires and harnesses to try to make the problem active, or re-occur.
This section should serve as a guideline for the technician.
- Intermittent Problems - Talk to the operator/driver. Be specific!
- Develop your own Driver Questionnaire (see Figure
Note: A full page copy of the questionnaire can be found in Appendix "10.4.7 Engine Diagnostic Questionnaire" .
Figure 1. Drivers Questionnaire
Ask the driver to answer the following questions before attempting to repair an intermittent problem, or a problem with symptoms but no diagnostic codes. Use this and the response as a guideline. Refer to Questionnaire Response Guideline found on page 1–6.
- How often does the problem occur? Can you and the driver take the vehicle and demonstrate the problem in less than 30 minutes?
- Has the vehicle been to other shops for the same problem? If so, what was done there?
- Did the radio, dash gages, or lights momentarily turn OFF when the problem occurred?
- Does the problem occur only at specific operating conditions? If so, at what load? Is it light, medium, or heavy?
- Does the problem occur at a specific engine operating temperature? If so, at what engine temperature?
- Does the problem occur at a specific engine operating altitude? If so, at what altitude?
- Does the problem occur only when above or below specific outside temperatures? In what temperature range?
- Does the problem occur during other conditions e.g. during or after rain, spray washing, snow?
- Did the problem occur at a specific vehicle speed? If so, at what vehicle speed?
- Does the problem occur at specific engine RPM? If so, at what engine RPM?
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.
- 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.
- 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.
- If other vehicle devices are affected, this indicates there may be something wrong with the ignition wiring.
- 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.
- Operate the engine at this temperature while attempting to duplicate the problem. Use the snapshot feature on the DDDL.
- If possible, troubleshoot the problem in this temperature range.
- If the problem seems to occur during or after the engine is subjected to rain/spray washing, thoroughly inspect the connectors for moisture entry.
- 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.
- 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.
|Series 60 EGR Technician's Manual - 7SE60|
|Generated on 10-13-2008|