Aftertreatment Diesel Oxidation Catalyst Efficiency
The MAXXFORCE-P200C (MaxxForce) diesel fault code means: Aftertreatment Diesel Oxidation Catalyst Efficiency. This is a serious severity code.
- Keep driving?
- Short distances only
- DIY difficulty
- advanced
- Estimated cost
- $1,800-$4,500
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Common Symptoms
- CEL
- Regen failures
- Derate
Probable Causes (Ranked by Likelihood)
- Failed / contaminated DOC Likely
- Coolant contamination from EGR cooler leak Possible
Step-by-Step Diagnostic Procedure
Scan DOC inlet / outlet temps during regen.
Replace DOC if efficiency lost permanently.
Frequently Asked Questions
What is P200C on a MaxxForce 11 (10.5L)?
P200C on a MaxxForce 11 (10.5L) (2008-2014) indicates: Aftertreatment Diesel Oxidation Catalyst Efficiency. This is a known fault code on the MaxxForce engine family and typically points to the causes listed above.
Can I drive with P200C on my MaxxForce?
Only drive short distances to reach a repair facility. Continued operation may cause further damage or progressive derate.
How much does it cost to fix MaxxForce P200C?
Repair cost is typically $1,800-$4,500 depending on the underlying cause and shop rate. Many MaxxForce faults (especially EGR cooler, head bolt, and VGT repairs) are major expenses that drove fleet owners to repower with Cummins or retire these trucks early.
P200C on Other Platforms
The same code ID appears across other engines, vehicles, and equipment. Diagnostic flow varies by platform — see the matching breakdown: