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TuningBot DTC Database · v4.37.15

P1138 Mercedes-Benz - Heated oxygen sensor (HO2S) 2 - range/ performance problem

Manufacturer-specific interpretation for Mercedes-Benz. All interpretations of P1138

P · PowertrainEmissionsOBD2

What P1138 means

P1138
Heated oxygen sensor (HO2S) 2 - range/ performance problem Mercedes-Benz · emissions Data confidence 62%

The control module judged the Heated oxygen sensor (HO2S) 2 behaviour implausible for the current operating conditions. This is the manufacturer-specific definition used by Mercedes-Benz.

Possible causes

  • Wiring
  • HO2S

Related and nearby codes

How to read P1138

P

Powertrain: engine, transmission and driveline systems.

1

Manufacturer-defined range: the meaning can differ between brands.

138

Specific fault index within the subsystem.

Frequently asked questions about P1138

What does P1138 mean?

Heated oxygen sensor (HO2S) 2 - range/ performance problem. The control module judged the Heated oxygen sensor (HO2S) 2 behaviour implausible for the current operating conditions. This is the manufacturer-specific definition used by Mercedes-Benz.

Is P1138 generic or manufacturer-specific?

P1138 is a manufacturer-specific code. In this database it is documented for: Mercedes-Benz. The same number can mean something different on other brands.

Can TuningBot remove P1138 at file level?

If the fault logic lives in the ECU calibration, yes: our DTC Removal file service disables the specific fault entry. Checksum correction is not included: it is a separate, optional service. Not sure whether your case qualifies? Request a free assessment and our engineers will check your ECU file.

Other file services

ECU tuningStage 1 dyno results for Mercedes engines See the results →

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