Error Code P042D: What It Means & What To Do?

<<See All OBD Codes

The error code P042D can be defined as Catalyst Temperature Sensor Circuit High Bank 1 Sensor 2. One of the most important pieces of emissions equipment on a vehicle is the catalytic converter. There are some exhaust gases which would pass through the catalytic converter which would then give rise to a chemical reaction. When this reaction has taken place, it would convert carbon monoxide, nitrogen oxides and hydrocarbon into harmless water as well as carbon dioxide.

Are you willing to learn something more about this trouble code? The performance of the catalytic converter temperature sensor circuit is monitored by the engine control module which performs the function of measuring the temperature of the catalyst. The catalyst temperature sensor functions by increasing their resistance with increasing the temperature of the exhaust gas. The ECM will then set the error code when the catalyst temperature sensor signal is not as per the factory specifications.

What causes this problem with the Catalyst Temperature Sensor Circuit High Bank 1

Sensor 2?

• Defaults in the oxygen sensor
• The PCM/PCM programming might be quirky
• Catalyst temperature sensor harness might be opened or shorted
• There can be poor electrical connection in the catalyst temperature sensor circuit
• Flaws in the catalyst temperature sensor
• Problems related to wiring
• The exhaust air/fuel mixture can be out of balance

1. Powertrain Control Module - There can be some issues with the Powertrain Control Module due to which you may see P042D code appearing over and over again. Visit us to buy best quality PCM online.
2. Oxygen Sensor - A lot of issues can arise do to defective Oxygen Sensor. Did you just see P042D code flashing? Now you know the reason why it is appearing. Get your Denso Oxygen Sensor inspected and replaced on time.
3. Diagnostic Tool - Willing to buy new Car Diagnostic Tools? You can always rely on us as we have best Automotive Diagnostic Tools for our customers.
4. Exhaust System Parts - Exhaust System Parts are important auto parts which need full care. Defective Exhaust System Parts can be a reason behind the flashing up of P042D code.
5. Catalytic Converter - OBD Code P042D can appear because of faulty Catalytic Converter.
6. Air Fuel Ratio Sensor - There can be some issues with the Air Fuel Ratio Sensor due to which you may see P042D code appearing over and over again. Visit us to buy best quality Air Fuel Ratio Sensor online.
7. Engine Control Module - Are you facing some faults in your Engine Control Module? Don’t worry and get them replaced or else P042D code can turn up.

You might be thinking that how would you diagnose these problems? We at Parts Avatar Canada would help you diagnose the major symptoms easily.

Common Symptoms

• Diminishing fuel economy
• There can be poor engine performance
• Increase in the overall emissions
• Illumination in the check engine light

Looking out for some ways with the help of which you can correct this fault code? Then you have arrived at the correct place. We are here to help you out, so you must check out the steps mentioned below as follows:

• Restore the quirky catalyst temperature sensor
• Wiring should be repaired or replaced properly
• A lot of problems can be caused due to programming error in the PCM, so you can always replace it
• Carefully check the electrical connection in the catalyst temperature sensor circuit

There is no need to get strained if your OBD Code is still flashing up as we are here at your service. Have a look at our superior variety of Oscilloscope, Obd2 Scanner, Car Scanner, Exhaust Catalyst and many more. Now all your problems would vanish within no time.

Here are some steps which you should follow in order to diagnose this fault code:

If you want to diagnose the P042D trouble code, then you should visually inspect the downstream oxygen sensor and the corresponding wiring. Look for loose connections, damaged wiring, etc. You should also inspect for exhaust leaks both visually as well as audibly.

A false oxygen sensor code can be cause due to an exhaust leak. If damage is found, repair as necessary, clear the code and see if it returns.

The next step would be to check for technical service bulletins regarding the issue. If nothing is found, you will need to move forward to step by step diagnosis of the system.

The following is a generalized procedure, as testing for this code varies between vehicles. To accurately test the system, you can always refer to a vehicle make/model specific diagnostic flow chart.

• Check for other DTCs

Oxygen sensor codes can often be set because of engine performance problems that cause an out of balance air/fuel mixture. If there are other DTCs stored, you can always address those first before proceeding with oxygen sensor diagnosis.

• Check Sensor Operation

This is best done using a scan tool, or better yet, an oscilloscope. Since most individuals don't have access to a scope, so we will cover oxygen sensor diagnosis using a scan tool. Connect the scan tool to the ODB port under the dash. Turn the scan tool on and choose the Bank 1 Sensor 2 voltage parameter from the data list. Bring the engine up to operating temperature and view the sensor operation on the scan tool in graph mode.

The sensor should have a steady 0.45 volt reading with only very small fluctuations. If it is not responding correctly then it should be replaced.

• Check the circuit

Oxygen sensors produce their own voltage signal which is sent back to the PCM. Before proceeding, you can always consult the factory wiring diagrams to determine which wires are which. To check for continuity between the sensor and PCM, turn the ignition key to the "off" position and disconnect the O2 sensor connector. Connect a digital multimeter set to ohms with the ignition off between the O2 sensor signal terminal on the PCM and the signal wire. If the meter reads out of limits (OL) there is an open circuit between the PCM and sensor that will need to be located and repaired. If the meter reads a numeric value, it means that there is continuity.

Next, you'll want to check the ground side of the circuit. To do this, turn the ignition key to the "off" position and disconnect the O2 sensor connector. Connect a digital multimeter set to ohms (with the ignition off) between the O2 sensor connector ground terminal (harness side) and chassis ground. If the meter reads out of limits (OL) there is an open circuit on the ground side of the circuit that will need to be located and repaired. If the meter reads a numeric value, there is continuity to ground.

Finally, you should check that the PCM is processing the O2 sensor signal properly. To do this, leave all the connectors attached and insert a back-probe meter lead into the signal terminal at the PCM. Set the digital multimeter to the DC volts setting. With the engine warmed up, compare voltage reading on the meter to that on the scan tool. If the two do no match, the PCM is likely faulty and there is a need to reprogram the powertrain control module.

Common Mistakes When Diagnosing The P042D Code

• There can be some faults in the catalytic converter temperature sensor
• Some faults in the wiring
• Powertrain control module might start failing