DTC P0134: Right Front Ho2S - No Activity Detected Or DTC P0154: Left Front Ho2S - No Activity Detected: Condition

DTC is set when front HO2S signal voltage does not exceed .55 volt for 94 seconds after engine has reached normal operating temperature (coolant temperature more than 158°) and engine speed is more than 1500 RPM. Possible causes are:

• Front HO2S malfunction.
• Front HO2S heater malfunction.
• Exhaust system leak.
• Open or short circuit between front HO2S harness connector(s) and PCM harness connector.
• Engine compression low.
• Engine malfunction.