OBD-II DTC · SAE J2012
U302D
Ignition Output On/Start
What U302D means
U302D is a standard SAE J2012 powertrain diagnostic trouble code with the defined meaning: Ignition Output On/Start. This is the OEM-agnostic definition; specific manufacturer interpretation may add detail (subsystem, bank, sensor location) but the core meaning is consistent across all OBD-II compliant vehicles since 1996.
Common symptoms when U302D is active
Pulled ignition timing, power loss under load, knock counter increment, knock sensor circuit MIL.
Can this code be suppressed via ECU tuning?
Whether this code is safe to suppress depends on the underlying cause. Diagnose first, suppress only after confirming the mechanical issue is benign or rectified.
How to remove U302D with Softechpro V5
Recommended service: Not recommended (suppression masks engine damage risk). Step-by-step workflow:
- Knock detection is engine-protective. Suppressing it lets pre-ignition destroy pistons.
- If the knock is false (knock sensor wiring fault): fix the wiring, not the code.
- If you must suppress for a track-only build, Softechpro V5's DTC OFF can mask the specific code — but use at your own risk.
Softechpro V5 supports 1,400+ ECU firmwares across Bosch (EDC15, EDC16, EDC17, MD1, MG1, ME7, MED17), Siemens / Continental (SID, SIMOS, EMS), Delphi (DCM, DDC), and Magneti Marelli platforms.