8 SDLG diagnostic codes on file — with the full diagnosis, repair steps, and field insights open to read free, no signup required.
Disclaimer: General reference information for trained, qualified technicians only. Codes and procedures vary by model, serial number and software version. Always follow the manufacturer's service manual and your site's safety procedures. Use at your own risk. Not affiliated with or endorsed by any manufacturer.
Find a SDLG code by searching below, or browse the table. Codes on file by system:
| Code | System | Symptom | Full fix |
|---|---|---|---|
| Code 1204 / E1204 | Transmission | Transmission Won't Shift / Stuck in 2nd | View fix |
| SPN 3226 FMI 04 | Aftertreatment / SCR | Amber DEF Lamp / 30% Engine Torque Derate | View fix |
| SPN 520215 FMI 07 | Transmission / Clutch | Machine Binds Up / Shifts Harsh into 2nd | View fix |
| SPN 520240 FMI 05 | Hydraulics / Pilot | All Working Joysticks Dead / Gate Down | View fix |
| SPN 520250 FMI 03 | Hydraulics / Boom | Boom Float Fails / Arm Moves Uncommanded | View fix |
| SPN 520300 FMI 09 | Communication | Throttle Unresponsive / Dash Displays CAN Error | View fix |
| SPN 522105 FMI 3 | Hydraulics | Engine Bog / Black Smoke on Any Dig | View fix |
| SPN 91 FMI 04 | Throttle / Cab | Throttle Pedal Dead / Engine Sits at 900 RPM | View fix |
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