DDEC III/IV Single ECM Troubleshooting

Section 6.1 Basics

Section 6.1

The following listed items should be checked prior to starting any troubleshooting:‪

  • Ensure engine serial number on the ECM matches the serial number on the cylinder block.
  • Walk around the vehicle. Look for obvious problems such as leaks (air or liquid).
  • Inspect ECM for worn isolators, debris or bolts lodged between ECM and cylinder block.
  • Broken wiring connectors.
  • Fuel Supply - Full on.
  • Fuel tank level.
  • Vehicle damage.
  • Investigate any prior repairs, if applicable.
  • 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.
  • Electrical system interference caused by a defective relay, ECM 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 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.

Section 6.1.1
ECM Programming

The following label is attached to the ECM. See Figure "ECM Label" .‪

Click to see this graphic in a separate window

Figure 1. ECM Label

  • Every DDEC system engine serial number has its own file in the DDC Mainframe.


    Failure to match the serial number on the engine with the ECM programming may result in incorrect calibration results and engine damage.‪

  • ECM programming must be done to match the serial number you are currently working on. Failure to do so may result in incorrect calibration and engine damage.
  • Programming a DDEC III ECM must be done with an engine file set up for the DDEC III system.
  • Programming a DDEC IV ECM must be done with an engine file set up for the DDEC IV system.
  • For a summary of features and how to change them, refer to "7 DDEC ECM Software Features" .

DDEC III/IV Single ECM Troubleshooting Guide - 6SE497
Generated on 10-13-2008

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