# Service bulletin TSB250204

A bulletin is a manufacturer's communication to its dealers, as NHTSA indexes it. The summary is NHTSA's. The document is the manufacturer's: read it at NHTSA. A bulletin is not a recall, and listing a model year does not mean every vehicle of it is concerned.

- Type: Service bulletin
- NHTSA id: 11026087
- Published by NHTSA: 2025\-12\-03
- Manufacturer's number: TSB250204
- Manufacturer's date: 2025\-11\-26
- NHTSA component: ENGINE

## NHTSA's summary

This Technical Service Bulletin describes the verification and resolution steps for the engine control module calibration which may contain a defect, resulting in an inability to clear fault code 3749 \(Aftertreatment 1 Outlet NOx Sensor \- Data Not Rational \- Drifted High\) after the root cause has been repaired.

## The document

- [NHTSA's copy of the document (PDF)](https://static.nhtsa.gov/odi/tsbs/2025/MC-11026087-0001.pdf)
- [If that address does not open, try this one](https://static.nhtsa.gov/odi/tsbs/2025/MC-11026087-9999.pdf)

The document is the manufacturer's. This site does not hold it.

## Components

Engine

## Vehicles listed

- CUMMINS B6.7

JSON: [/v1/bulletins/11026087](/v1/bulletins/11026087)

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