What does it mean when an O2 sensor has high voltage?
The high voltage condition from the O2 sensor is indicating a lack of oxygen in the exhaust or other related problems, such as a leaking fuel injector or a broken up catalyst inside.
How do you fix P0420 Catalyst System Efficiency Below Threshold Bank 1?
What repairs can fix the P0420 code?
- Replace muffler or repair leaks in the muffler.
- Replace exhaust manifold or repair leaks in the exhaust manifold.
- Replace exhaust pipe or repair exhaust pipe leaks.
- Replace catalytic converter (most common)
- Replace engine coolant temperature sensor.
- Replace front or rear oxygen sensor.
What does the OBD-II P0420 error code mean?
The definition of the OBD-II P0420 code is “Catalyst System Efficiency Below Threshold (Bank 1)”. When the ECU stores this code, it means that the catalytic converter is not operating at maximum efficiency and may need replacement.
What does P0420 mean on a catalytic converter?
P0420 means that the efficiency of the catalytic converter is below the threshold. The ECM uses two O2 sensors, one in the front and one in the back of the catalytic converter to measure the efficiency. If the efficiency is low, the P0420 code will be triggered.
When does the ECM set the P0420 code?
When the ECM/PCM sees the downstream O2 sensor switching at or near the same rate as the upstream O2 sensor, it sets the P0420 code. What Does the P0420 Code Mean?
What does code p0138 on O2 sensor mean?
A code P0138 may mean that one or more of the following has happened: 1 Faulty O2 sensor 2 Short to battery voltage in O2 sensor signal circuit 3 High fuel pressure (not as likely)
What does the P0420 code on the O2 sensor mean?
The P0420 code means that rear O2 sensors report to the engine control module that the catalytic converter is not doing it’s job properly. The rear O2 sensor is comparing the signal from the front O2 sensor. How to clear code P0420? To clear the P0420 code you need to use an OBD2 scanner.
A code P0138 may mean that one or more of the following has happened: 1 Faulty O2 sensor 2 Short to battery voltage in O2 sensor signal circuit 3 High fuel pressure (not as likely)
How does a P0420 readiness monitor test work?
During a P0420 readiness monitor test, the ECM will purposely and rapidly command a very rich and very lean mixture to force the downstream sensor to read the excess fuel or oxygen. Then it will stop the excessive air/fuel and watch the downstream sensor again, looking for a steady reading.
How can I fix the P0420 code on my catalytic converter?
To fix the P0420 code, you need to diagnose what is causing the trouble code. Start with inspecting and diagnosing your catalytic converter and continue with checking the O2 sensors. What can cause a P0420 code? A bad catalytic converter is the most common cause of the p0420 code.