DTC P3400 Dodge

HO2S-21 (B2 S1) Slow Response

HO2S-21 (B2 S1) Slow Response

Description

Engine started, engine idling in closed loop, and the PCM detected the HO2S-21 response time from rich-to-lean or from lean-to-rich was 1.1 second or longer during the CCM test. Note: This fault must be detected at least 3 times at idle speed.

Cause and Solution

HO2S signal circuit is open or shorted to groundHO2S element is contaminated, or HO2S heater has failedIntake air leaks, exhaust manifold leaks or PCV system leaksMAF sensor out of calibration (it may be dirty or contaminated)

Video Guide

Duration: PT4M4S | Uploaded: 2020-08-07

Diagnostic Info

  • DTC Code: P3400
  • Brand: Dodge
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