Error Code P202C: What It Means & What To Do?

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Are you looking for information with respect to the P202C error? Then you are at the right place? This error signifies a defective PCM and is known as reductant tank heater control circuit high. The soot emission can be reduced by using DPF which is installed in newer vehicles. Up to an effective temperature, the DEF fluid is heated by the reductant tank heater. The P202C error will be stored in the vehicle if the PCM finds the malfunctioning of the reductant tank heater.

This is a general type of trouble code which is applicable to many OBD-II vehicles. But it is not restricted to vehicles like Volkswagen, Mercedes-Benz, Dodge, Audi, etc. Thought it is general, the repair steps will slightly vary based on the year, make, model and configuration of the powertrain. If the P202C error code is stored, then it means that the PCM has found high voltage in the control circuit for the reductant tank heater. The reduction of the exhaust emission is done by the catalyst system though there might be some applications which are well-equipped with NOx trap. EGR systems will go a step ahead to further minimize the NOx. However, it will impossible for today’s larger and powerful diesel engine’s to meet the strict federal emission standards by the US along with the EGR, DPF/catalytic converter, and NOx trap all alone. For this purpose, the selective catalytic reduction system was introduced.

SCR system will insert a reductant compound or DEF into the exhaust which is in front of the DPF, NOx trap or the catalytic converter through the reductant injection valve. The DEF injection which is correctly timed will raise the temperature of the filtration element and will allow it to perform effectively. The longevity of the filtration element will be enhanced and the harmful exhaust emission which is to be released into the atmosphere will be less. A stand-alone controller or PCM monitors the entire SCR system. In order to identify the approximate time for DEF injection, the controller will monitor the O2, NOx, and exhaust temperature sensors. In order to maintain the exhaust temperature within the acceptable parameters, accurate DEF injection is needed and the pollutant filtration can be optimized. To prevent the DEF from freezing during risky cold temperature, reductant tank heaters are used which is found in and around the DEF reservoir.

What causes this problem with the Reductant Tank Heater Control Circuit High?

• The reductant tank heater element might be faulty.
• There might be an opening or the circuit might be short in the reductant tank heater control circuit.
• The SCR controller might be bad or a programming error might arise in the PCM.

1. Powertrain control module - Any corrosion or break in the internal wiring harness can cause a short in your PCM. If you’re PCM is shorted, then you must change the powertrain control module (ECM) as soon as possible to avoid the P202C error code
2. Tank heater - A faulty or defective tank heater has to be replaced or changed quickly to avoid further troubles.
3. Diesel particulate filter - If the DPF is damaged, then the fuel economy will be very low. Get rid of the faulty DPF to avoid P202C error.
4. Engine control module - The ECM helps in generating output signals to control relays, actuators, and solenoids. If there is no proper output signal or if it is erratic then the ECM might be faulty. Fix the faulty ECM instantly.
5. Exhaust system - The performance of the vehicle during startup will be erratic. It one such situation it’s best to replace the exhaust system as it might be defective.
6. Injection valve - It is easy to get rid of the P202C error code when the faulty or broken injection valve is replaced as soon as possible by shopping online from PartsAvatar.

Willing to know some common symptoms of OBD Code P202C? Your wish is our demand. Have a look at them below:

Common Symptoms

• Decreased fuel efficiency.
• There will be adequate black smoke from the vehicle’s exhaust.
• Reduced engine performance.
• SCR related other error codes.

We have listed out some ways which would help you to correct the occurrence of OBD Code P202C. They are mentioned here as follows:

• Replacing the faulty reductant tank heater element.
• Fixing the opening or short circuit in the reductant tank heater control circuit.
• Replacing the defective SCR controller.
• PCM reprogramming has to be done.

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 powertrain control module, tank heater, filter, engine control module, ECM module, PCM module, sensors and many more. Now all your problems would vanish within no time.

It is essential to diagnose this fault code. Here are some steps which a mechanic should follow for diagnosing the problem that triggered a P202C code to be stored:

• Initially, the mechanic will use a scanner to check for the stored error codes.
• He will now connect a scanner to the diagnostic port of the vehicle and recover the stored codes and freeze frame data.
• These data are usually obtained as they can help him with further diagnostic process.
• Firstly the mechanic will check the reductant tank heater element. If there are any faults or defects, it will be repaired.
• If there are no errors, then the mechanic will check the electrical connection as well as the harness of the reductant tank heater control circuit for any openings or shorted circuit.
• He might also check if there are any other stored error codes.
• If there are any errors, the mechanic will repair them immediately.
• As a final step, the mechanic will inspect the powertrain control module as well as the SCR controller if it is broken or damaged. If it is broken, the mechanic will carry out the repair process.
• After every component is repaired and when the diagnosis process is properly done, the mechanic has to test drive your vehicle again see if the engine light turns on or if the error code still appears.
• This can help him to locate the area as to where the error was stored in the vehicle.

Common Mistakes When Diagnosing the P202C Code

• Malfunctioning of the powertrain control module.
• Failure of the reductant tank heater.
• Reductant tank heater control module is defective.
• The wires may be problematic.