Detroit Diesel Fault Code

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DDC 1215 (Legacy)

Shift Hunting / Speedo Dead.

System

Network

Symptom

Shift Hunting / Speedo Dead.

Diagnosis & fix steps

LOGIC: J1939 Data Link - Transmission Data Missing. ACTION: Check the 2-pin twisted pair wiring between the MCM and the Trans ECU (TCM).

Red Seal field insights

Specs: 60 Ohms resistance across the CAN pins. PRO-TIP: On Freightliner/Western Star chassis, the harness often rubs through on the top of the transmission bell housing.

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