DDEC III/IV Single ECM Troubleshooting – Section 55.3 Troubleshooting Flash Code 55

Section 55.3
Troubleshooting Flash Code 55

The following procedure will troubleshoot Flash Code 55.‪

Section 55.3.1
Check J1939 Data Link

Perform the following steps to check for J1939 data link fault.‪

1. Is this a J1939 transmission/engine application?
   1. If yes, contact Detroit Diesel Technical Service.
   2. If no, use programming station and go to "update customer calibration" and select transmission to manual, or correct transmission. Save changes. Refer to "55.3.3 Verify Repairs" .

Section 55.3.2
ECU Code Check

Perform the following steps if code 216/14, missing other ECU displays. This indicates DDEC ECM has lost its connection with other ECU devices and a lost or shorted J1939 data link. ‪

1. If code 86/14 displays also, there is a fault with the smart cruise. Contact OEM for instructions.
2. If code 84/12 displays, the fault is with the programming of the ECM, or a short exists to the J1939 data link. Contact OEM for VSS (Vehicle Speed Sensor) troubleshooting.

Section 55.3.3
Verify Repairs

Perform the following steps to verify repairs.‪

1. Start engine.
2. Plug in DDR.
3. Read codes.
   1. If active codes 216/14 or 231/12 are not logged, troubleshooting is complete.
   2. If active codes 216/14 or 231/12 are logged, contact Detroit Diesel Technical Service. Check DDR software level. Update DDR software if current level is 1.2.