91 Generic 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.
| Code | System | Symptom | Full fix |
|---|---|---|---|
| P0414 | Emissions | Secondary Air Fuse Blown | View fix |
| P0415 | Emissions | MIL On | View fix |
| P0416 | Emissions | MIL On | View fix |
| P0417 | Emissions | Air System Relay Clicks Rapidly | View fix |
| P0418 | Emissions | Loud Whining Pump Fails to Run | View fix |
| P0419 | Emissions | MIL On | View fix |
| P0420 | Emissions | Check Engine Light Only / No Performance Loss | View fix |
| P0420 | Emissions | MIL Illuminated / No Performance Loss | View fix |
| P0421 | Emissions | MIL On / Catalyst Test Incomplete | View fix |
| P0422 | Emissions | MIL On | View fix |
| P0423 | Emissions | MIL On | View fix |
| P0424 | Emissions | MIL On | View fix |
| P0430 | Emissions | Check Engine Light On | View fix |
| P0431 | Emissions | MIL On | View fix |
| P0432 | Emissions | MIL On | View fix |
| P0433 | Emissions | MIL On | View fix |
| P0434 | Emissions | MIL On | View fix |
| P0440 | Emissions | Fuel Smells / Check Engine Light Only | View fix |
| P0441 | Emissions | Rough Idle after Fueling / MIL On | View fix |
| P0442 | Emissions | Check Engine Light Only | View fix |
| P0443 | Emissions | MIL On / Hard Idle Hunt | View fix |
| P0444 | Emissions | MIL On | View fix |
| P0445 | Emissions | EVAP Fuse Blows Instantly | View fix |
| P0446 | Emissions | Hard to Fuel / Gas Pump Clicks Off | View fix |
| P0447 | Emissions | MIL On Only | View fix |
| P0448 | Emissions | MIL On Only | View fix |
| P0449 | Emissions | MIL On Only | View fix |
| P0450 | Emissions | MIL On Only | View fix |
| P0451 | Emissions | MIL On Only | View fix |
| P0452 | Emissions | MIL On Only | View fix |
| P0453 | Emissions | MIL On Only | View fix |
| P0454 | Emissions | Erratic Fuel Gauge / Periodic MIL On | View fix |
| P0455 | Emissions | Check Engine Light / Gas Cap Loose Lamp | View fix |
| P0465 | Emissions | MIL On Only | View fix |
| P0466 | Emissions | MIL On | View fix |
| P0467 | Emissions | MIL On | View fix |
| P0468 | Emissions | MIL On | View fix |
| P0469 | Emissions | Venting System Shudders Int. | View fix |
| P2002 | Emissions / DPF | DPF Warning Lamp / Low Fuel Economy | View fix |
| P204F | Emissions | Reduced Power / DEF Lamp | View fix |
| P20EE | Emissions / SCR | AdBlue Lamp / Active Derate Warning | View fix |
Same codes keep coming back?
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