DDEC III/IV Single ECM Troubleshooting – Section 72.3 Troubleshooting Flash Code 72

Section 72.3
Troubleshooting Flash Code 72

The following procedure will troubleshoot Flash Code 72. ‪

Section 72.3.1
Overspeed

Perform the following steps to troubleshoot overspeed.‪

1. These codes indicate the vehicle speed has exceeded the limits programmed into the ECM. Verify cruise control and VSS information.
   1. Code 84/0 - Overspeed with fuel limit has been exceeded.
   2. Code 84/11 - Overspeed without fuel limit has been exceeded.
2. Limits are a reasonable distance above the road speed limit.
   1. If the limits are a reasonable distance, go to step 3 .
   2. If the limits are not a reasonable distance above the road speed limit, change the limits and perform the test. Refer to "72.3.2 Test" .

   Note: For information regarding overspeed limits, refer to "7.1.29 Vehicle Overspeed Parameters" .

3. Fuel Economy Incentive feature configured recently.
   1. If configured recently, review the limits. W/FEI limits may need to be increased.
   2. If not configured recently, the conditions are normal. The vehicle has exceeded speed limits set.

Section 72.3.2
Test

Perform the following steps to troubleshoot overspeed.‪

1. Start and run the engine.
2. Perform a road test.
   1. If the overspeed condition has disappeared, troubleshooting is complete.
   2. If the overspeed condition still exists, review this section from the beginning to find the error. Refer to "72.3.1 Overspeed" .