Mitsubishi P0420
10 Outlander, 2009-10 Lancer, 2010 Lancer Sportback Provides instructions to reprogram the ECM to correct false MIL relating to P0420. TSB-12-13-006 ECM Reprogramming for Engine Sy
Quick answer
Mitsubishi P0420: 10 Outlander, 2009-10 Lancer, 2010 Lancer Sportback Provides instructions to reprogram the ECM to correct false MIL relating to P0420. TSB-12-13-006 ECM Reprogramming for Engine Sy
This page separates verified manufacturer/regulator evidence from supporting material. Unsupported causes, repairs or safety conclusions are not guessed.
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1. What does Mitsubishi P0420 mean?
Mitsubishi P0420: 10 Outlander, 2009-10 Lancer, 2010 Lancer Sportback Provides instructions to reprogram the ECM to correct false MIL relating to P0420. TSB-12-13-006 ECM Reprogramming for Engine Sy
2. Technical explanation
The identity of P0420 is verified for Mitsubishi. Available evidence does not yet establish a narrower subsystem or component-level failure.
3. What system is affected?
Not yet established by verified evidence.
4. How serious is this code?
Not yet established by verified evidence. Urgency must be based on the exact vehicle warning and official guidance.
5. Mitsubishi P0420 symptoms you may notice
Not yet established by verified evidence.
6. Possible causes of Mitsubishi P0420
Not yet established by verified evidence. A diagnostic identifier alone is not proof that a specific component has failed.
7. Can I drive with Mitsubishi P0420?
Not yet established by verified evidence.
8. Can I charge with Mitsubishi P0420?
Not yet established by verified evidence.
9. What you can safely do
- Preserve the exact diagnostic code and any accompanying vehicle warning before clearing anything.
- Follow the manufacturer instructions shown in the vehicle or owner/service documentation.
- Do not open or work on high-voltage components unless you are qualified and equipped for high-voltage service.
10. How to troubleshoot Mitsubishi P0420
- Record the exact code, warning text, vehicle model, model year, and operating condition when it appeared.
- Check the verified manufacturer or regulator source linked on this page for code-specific instructions.
- Avoid replacing parts based only on the code; code-specific component tests are not inferred when evidence does not provide them.
- Escalate to qualified service when the warning persists, affects driving/charging, or manufacturer guidance requires service.
11. When to contact service
Qualified service should be contacted if the warning persists, returns after a normal manufacturer-permitted restart, or affects driving or charging.
12. What the service center may check
Not yet established by verified evidence.
13. Possible repair or resolution for Mitsubishi P0420
Not yet established by verified evidence.
14. Affected vehicles
- Mitsubishi Outlander · 2012–2020 · US
15. Related TSBs / service bulletins
- NHTSA: NHTSA Manufacturer Communication PDF 10170087: TT192
16. Recall information
No recall relationship is established by verified evidence.
17. Official manufacturer information
t specification entry . TSB-12-00-021 VIN Plate & Chassis Code Charts Update-SMR 2013 Outlander Sport/RVR Updates VIN plate information to correct model year. TSB-12-13-005 ECM Reprogramming for False MIL (DTC P0420) 2008-10 Outlander, 2009-10 Lancer, 2010 Lancer Sportback Provides instructions to reprogram the ECM to correct false MIL relating to P0420. TSB-12-13-006 ECM Reprogramming for Engine System Service Required Illuminated - Revised 2008-11 Lancer Evolution 2009-11 Lancer Ralliart 2009-11 Lancer Sportback Ralliart Provides instructions to reprogram the ECM to correct Engine System Service Req'd illumination on MIL. TSB-12-51-004 Liftgate Spoiler Side Gasket-SMR 2011-12 Outlander Sport/R
- NHTSA: NHTSA Manufacturer Communication PDF 10170087: TT192 · official_tsb
19. Mitsubishi P0420 frequently asked questions
What does P0420 mean?
Mitsubishi P0420: 10 Outlander, 2009-10 Lancer, 2010 Lancer Sportback Provides instructions to reprogram the ECM to correct false MIL relating to P0420. TSB-12-13-006 ECM Reprogramming for Engine Sy
Can I drive with P0420?
Not yet established by verified evidence.
Can I charge with P0420?
Not yet established by verified evidence.
Does P0420 require service?
Qualified service should be contacted if the warning persists, returns after a normal manufacturer-permitted restart, or affects driving or charging.