P20A1 OBD Error Code: Problem & Solutions

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The trouble code P20A1 can be explained as Reductant Purge Control Valve Performance. This diagnostic fault code is a generic powertrain code, which means that it would apply to the OBD-II equipped vehicles. The specific repair steps can vary as it depends upon the vehicle make and model. The engine control module, powertrain control module or the transmission control module monitors this circuit depending upon the particular automobile.

If the engine control module would detect a variation in the voltage coming from the reductant purge control valve circuit that is outside the parameters set by the automobile manufacturer, then it would store the P20A1 error code. This would also give rise to the illumination of the check engine light.

What causes this problem with the Reductant Purge Control Valve Performance?

• Faulty PCM or ECM
• There can be inoperative fuse or fuse-able link
• Unusable control module ground strap
• Imperfect wiring
• Quirks in the reductant purge control valve

1. Automatic Transmission Module – Sometimes the automatic transmission module is unable to communicate or correctly anticipate the speed of the vehicle and thus creates difficulty in gear shift leading to sluggish acceleration, throttle response and stalling. Thus can also hamper a lot of components physically and thus must be check for and replaced, if required.
2. Engine Control Module - If there is any corrosion or breaks in the internal wiring of the harness, then it can cause a short in the ECM or can also cause corrosion in the ECM through the wiring harness. You can always rely on us as we have best auto parts for our customers.
3. Powertrain Control Module - The onboard computer, or powertrain control module is the brain of the engine control system. Now if the brain is not working properly, then neither is the car engine. Get it replaced before the situation gets worse.
4. Fuel Injector – The fuel injectors are important component of the fuel delivery system that helps in proper utilization of the fuel entering the engine. This not only helps in taking care of the air to fuel ratios in the engine, helping the combustion process but also enhances the performance. Thus, replace faulty injector now!
5. Exhaust Gas Recirculation Valve - It is auto part commonly found on many road going automobiles. It is a part of the vehicle’s exhaust gas recirculation (EGR) system, an emissions system that is designed to recirculate exhaust gases back into the vehicle’s intake so that it can reduce cylinder temperatures and NOx emissions. Purchase top notch exhaust gas recirculation valve from us at economical prices.
6. Electronic Control Unit - Is your car jump starting on reverse polarity? Or are you facing some intermittent starting issues? If yes, then it indicates that your electronic control unit is bad. So it is very important to replace the defective electronic control unit with us at equitable prices.
7. Diagnostic Tools - Buy quality diagnostic tools to check and diagnose OBD code P20A1 error with the help of experienced mechanic. Visit us today!

There could be countless symptoms which that would accompany with this fault code. Willing to know some common symptoms of OBD Trouble Code P20A1? Your wish is our demand. Have a look at them below:

Common Symptoms

• Check engine light might come into signal
• Decrease in the overall fuel efficiency
• The engine performance might start declining

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:

• It is essential to restore the flawed wiring
• Repair or replace the quirky ground straps
• Rehabilitate the defaults in the reductant purge control valve
• Carefully adjust the faults in the powertrain control module
• Recondition the non-functioning fuse or fuse-able link
• Make sure to clean the corrosion from connectors
• You can always restore the PCM or ECM

Don’t get tensed if you are still facing any of these issues as we care for our customers and that’s why we offer a good range of pcm, ecm, reductant purge control valve, diesel exhaust fluid, reductant tank heater, DEF system, reductant pump, reductant purge control valve, pressure sensor, temperature sensor, filters, reductant injector, fuse able link and a lot more. We are sure that now all your issues would be resolved.

It is essential to diagnose this fault code. Here are some steps which a mechanic should follow for diagnosing the problem that triggered a P20A1 code to be stored:

• You must always start with a technical service bulletin search for your particular vehicle.
• Advanced diagnostic steps become very vehicle specific and may require the appropriate advanced equipment and knowledge to perform accurately.
• We include basic steps below but refer to a vehicle year/make/model/powertrain specific repair guide for specific steps for your vehicle.
• Then after that the next step is to find all the constituents which are related to the reductant purge control valve circuit and then search for obvious physical damage.
• As per the particular vehicle, the DEF system might incorporate several constituents which include a reductant pump, purge valve, pressure sensor, integrated level sensor, temperature sensor, system heaters, filters, an electrically controlled reductant injector and a reservoir.
• A thorough visual inspection should be performed to inspect the related wiring for obvious defects such as scraping, rubbing, bare wires, or burn spots.
• Then after that it is important to examine the connectors and connections for security, corrosion and damaged pins.
• The process should include all wiring connectors and connections to all components including the PCM or ECM.
• Consult the particular tech data for the automobile to check if a fuse or fuse-able link is incorporated into the circuit.
• The advanced steps become very automobile specific and need the appropriate advanced equipment to perform correctly.
• These procedures require a digital multi meter and the specific technical references for the vehicle. Now in this case, a pressure gauge may also be needed to assist the process of troubleshooting.
• The reference voltage and the acceptable ranges might differ depending upon on the particular vehicle and the circuit configuration.
• Particular technical data will include troubleshooting charts and the appropriate sequence to follow assisting you with correct diagnosis.
• Now if an absence of a power source or ground is identified in this process, then there would be a need of continuity testing to inspect integrity of the wiring, connectors and other constituents.
• Make sure to perform continuity tests with the power removed from the circuit and the normal readings for wiring and connections should be 0 ohms of resistance.
• Resistance or no continuity would indicate that there are some faults in the wiring, so it should be repaired or restored.
• Then a continuity test should be performed from the PCM or ECM to the frame will confirm the serviceability level of ground straps and ground wires.
• The presence of resistance would indicate that the connection is loose or there is corrosion.

Common Mistakes When Diagnosing The P20A1 Code

• Malfunctioning powertrain control module
• There can be a failure in the reductant purge valve
• Wiring problems