We’ve worked on several Mitsubishi L200 diesels over the years, but this one was a great reminder that not every fault is caused by the most obvious problem.
We were called out to our friends at Lockley Contracting in Mount Hawke, near Porthtowan, to carry out a DPF delete on a customer’s Mitsubishi L200. The software work was completed successfully—but the vehicle was still displaying emissions faults and a regeneration warning light.
Why the Regen Light Didn’t Clear
On certain Mitsubishi L200 models, the DPF regeneration warning is not triggered by the DPF itself.
Instead, it’s caused by:
- Overfilled engine oil
- Diesel contamination in the oil
- Failed or repeated regeneration attempts
When a vehicle repeatedly attempts to regenerate, diesel can pass into the oil, increasing the oil level. Once this happens, no amount of ECU coding alone will clear the warning light.
The Correct Fix: Software + Mechanical Work
To fully resolve the issue, the following steps were required:
✔️ Physical oil and filter change
✔️ Oil service reset
✔️ DPF regeneration warning reset
Only once the oil level was corrected would the ECU allow the regen warning to clear.
As a bonus, the oil change also eliminated excessive smoke, which had been caused by diesel-diluted oil burning off.
👉 Learn more about our DPF Delete Services and how they work alongside proper diagnostics.
Why Diagnosis Matters More Than Guesswork
This job is a perfect example of why:
Symptoms don’t always point to the root cause
A regen light doesn’t always mean:
- A failed DPF
- A bad sensor
- A software fault
Sometimes, the issue is mechanical, and software alone won’t fix it.
At Kernowsport, we:
- Diagnose before we modify
- Explain the cause, not just the cure
- Work alongside trusted local garages when mechanical work is required
Trusted by Cornwall’s Trade & Contractors
We regularly support:
- Contractors
- Fleet operators
- Agricultural and commercial vehicle owners
Working closely with garages like Lockley Contracting, we help keep working vehicles earning money, not sitting in limp mode.
👉 If you’re a garage or fleet operator, see our Trade & Garage Support services.
Need Help With an L200 or Working Vehicle?
If your pickup or van has:
- Persistent regen or emissions warnings
- Excessive smoke
- Repeated DPF issues
📞 Contact Kernowsport
📍 Based in Hayle, Cornwall
🚐 Mobile service available across the county
Sometimes the fix isn’t just software—it’s knowing when software isn’t enough.












