DTC P0134: Front Ho2S Circuit, No Activity Detected: Condition

DTC is set when front HO2S signal voltage does not exceed .55 volt for 120 seconds after engine coolant temperature has reached more than 158°F (70°C) and engine speed is more than 1500 RPM. Powertrain Control Module (PCM) checks front HO2S operation during HO2S/TWC monitor repair verification drive mode. See DRIVE MODES  under SELF-DIAGNOSTIC SYSTEM. This is a continuous monitor. MIL is illuminated when PCM detects malfunction during 2 consecutive drive cycles. Possible causes are:

• Front HO2S.
• Exhaust leak.
• Open or short circuit between front HO2S and PCM.
• Low engine compression.
• Engine malfunction.