What Is An Audi P208A Code Warning

Audi / By
  • Faulty reducant pumps
  • Wiring and harness for the circuit for the reducant pump
  • Reductant pump electrical connections are inadequate.
  • Error in the SCR controller, PCM, or programming

Replace/Repair These Parts To Fix OBD Code P208A

  • The engine control module isn’t always the culprit.
  • Module for Powertrain Control – Powertrain
  • Diagnostic Tool: It is recommended to

Professional has the skills and understanding to use such tools effectively.

  • The Electronic Control Unit (ECU) keeps an eye on
  • Recirculation Valve for Exhaust Gas: Did

Configure the check engine light to alert the driver to the problem. Spend less time and get

Pump for Diesel Exhaust Fluid: Diesel exhaust fluid

Symptoms Of OBD Error Code P208A

Displaying the OBD Code P208A. Here, they are described as follows:

  • The check engine light can begin flashing.
  • Fuel efficiency was impacted
  • Engine performance dropped
  • There may occasionally be no outward signs.
  • Black smoke could begin to erupt from the

How To Correct P208A Reductant Pump Control Circuit/Open

With the following assistance, you may resolve OBD Code P208A:

  • Replace or fix any faulty, damaged, or
  • Rehabilitate the reduction defaults
  • You must correct the damaged or corroded
  • Be sure to fix the malfunctioning exhaust system.
  • Adjust the exhaust’s flaws carefully.
  • Restore the malfunctioning terminals to operation

Easy Diagnosis Of Engine Error OBD Code P208A

Should be carried out to identify this error code:

  • The first step is to visually inspect the
  • Check the connector visually for damage.
  • The technician needs to test the system once more to ensure
  • The technician or mechanic will utilize a
  • Following a thorough examination, each
  • He will be aware that a temporary state
  • Managing intermittent conditions is quite difficult.
  • Verify the exhaust gas circuits.
  • Restore the circuitry’s defaults.
  • After that, it’s crucial to look at the
  • To test, a heated element should be utilized.
  • If this weren’t going to happen, it would
  • The EGTS/EGPS voltage, measured at the
  • If the EGTS/EGPS voltage reading is now
  • It would be necessary to swap out or reprogramme
  • The reductant may have various faults.
  • If the mechanic determines there isn’t
  • The P208A error code would begin to display.
  • Sometimes a mechanic may not understand the
  • Damaged or open reductant pump circuit
  • The majority of mechanics simply don’t check the

A reductant pump control is what?

The system for delivering reductant consists of a pump that draws reducer from a tank, an injector that adds reducer to the exhaust gas, and a heater that warms the reductant in the tank. An ECU is a component of a control system that uses detected temperatures to operate the pump, injector, and heater.

What does P20B9 code mean?

Reductant Heater “A Control Circuit/Open” is the meaning of the diagnostic trouble code (DTC) P20B9. When the reductant heater doesn’t function as planned, this code is set. If the powertrain control module (PCM) fails to detect voltage in the reductant heater A’s control circuit, the P20B9 engine code may also be set.

How can I resolve my P20B9 error?

The reductant temperature sensor detects when the temperature of the diesel exhaust fluid falls below the freezing point of 12F (-11C), and the powertrain control module subsequently instructs the glow plug control module to provide voltage to the heating element. The heating element will melt the liquid reductant inside the reductant heater as well as the sender assembly reservoir during the chilly ambient temperature.

  • Potentially defective is the reductant heater.
  • Either the reducer heater harness may be shorted, or the circuit may have a gap.
  • Very shoddy electrical connection in the circuit for the reducer heater.

Replace/Repair These Parts To Fix Code P20B9

  • Temperature Sensor: A faulty temperature sensor is indicated by the check engine and DPF lights flashing. Remove it as quickly as you can.
  • Diesel Exhaust Fluid (DEF): Dirty DEF can clog filters, create pressure and temperature differentials, and otherwise negatively impact an engine’s overall performance. To prevent the P20B9 error code, the filthy DEF needs to be rapidly replaced.
  • Powertrain Control Module (PCM) malfunctions are brought on by incorrect sensor and other control module input.
  • Get the greatest deal from Parts Avatar on the new PCM you need for your faulty one.
  • Engine performance problems may result from a shorted or open circuit in the reductant heater. The damaged reductant heater should be replaced to resolve the P20B9 problem.
  • Glow Plug: If the glow plug is destroyed, the engine may start slowly or hesitantly. Get the greatest deal on the appropriate replacement for the broken glow plugs from PartsAvatar.

Symptoms Of The OBD Error Code P20B9

Understanding an issue’s symptoms is crucial since only then will you be able to find a solution. Due to this, we have included some of the main OBD Code P20B9 symptoms below:

  • It is impossible for the DPF to regenerate.
  • Either the engine light or the warning light of the service engine will be on, and you will notice which one is on.

How To Correct P20B9 Reductant Heater A Control Circuit/Open

The OBD Code P20B9 can be fixed in a number of methods, some of which are listed below:

  • Replacing the damaged control circuit for the reductant heater “A”.
  • It is urgent to solve the reductant heater ‘A’ control’s opening or shorted circuit.
  • Replace the unclean diesel exhaust fluid as soon as possible.
  • Changing the damaged glow plugs.

You don’t need to worry because Parts AvatarCar Parts Online is here to assist you! For the benefit of our valued customers, we offer high-grade temperature sensors, diesel exhaust fluid, powertrain control modules, reductant heaters, diesel glow plugs, engine control modules, body control modules, and much more.

Easy Diagnosis of Engine Error OBD Code P20B9

You should take the following actions to diagnose this P20B9 error code:

  • The P20B9 error code solenoid valve will be activated by the engine control module, the powertrain control module, and the engine system together. This will change the timing of the valve between high and low by controlling the oil control pressure to the engine mechanism that is installed in the valve system.
  • The P20B9 error code will be saved in the car if the engine system has an opening or short circuit.
  • This type of error code is a general one, and diagnosing it and fixing it are both straightforward tasks.
  • Given the multiple circuits involved, it is better to leave the job to the qualified experts.
  • The mechanic will scan the vehicle’s issue codes whenever this error occurs using a scanner. However, a skilled specialist will check for an advanced diagnostic procedure using a sophisticated scanner like Autohex.
  • If the reductant heater is damaged, corroded, or broken, the mechanic will thoroughly examine it. If it is broken, it will be replaced right away.
  • The mechanic will then inspect the reductant heater’s harness for any potential damage and check for any openings or short circuits. This component will be repaired right away because any damage to it could lead to the error code being stored.
  • In a very unusual instance, the mechanic will discover that the powertrain control module needs to be changed right away.
  • Before continuing with the P20B9 error code, any other error codes that may be present must be fixed first.
  • After the diagnosis, it is wise to reset the code, and the car needs to be tested to see if the problem has been fixed.
  • The mechanic will be able to locate the issue by giving the car a test drive.

What is the purpose of a reducer tank heater?

The DEF Fluid is heated more effectively by the Reductant Tank Heater. The Reductant Tank Heater will not be functioning properly if the engine control module (PCM) detects this, and it will set code P202B.

What is a control performance for a reductant heater?

A part used to keep diesel exhaust fluid from freezing or crystallizing in cold climates is the reductant heater. It is typically found in the reducer injector supply pipe and/or the diesel exhaust fluid filter reservoir (s).

The meaning of service exhaust fluid system

Service When a Diagnostic Trouble Code (DTC) for the DEF system sets, which is interpreted as system tampering, Exhaust Fluid System (Tamper) displays. When the DEF tank has a remaining range of 1,000 miles (1,609 km) or less, the Exhaust Fluid Range X MI (KM) display appears.

Where is the def heater?

Even though the EGR system is quite good at lowering NOx emissions from engine combustion, the current NOx emissions requirements call for further steps to further minimize this pollutant. For it, the Selective Catalytic Reduction (SCR) system is employed. Diesel Exhaust Fluid (DEF) is first injected into the exhaust stream to begin the SCR process. DEF, DEF system components, and DEF dosing procedure are all covered in this article. When we cover the SCR system, the chemical reactions that happen are covered.

  • Is a pre-mixed liquid that contains 32.5 percent urea and 75% purified water.
  • Nitrogenous compounds like urea and water easily break down into ammonia.
  • DEF’s freezing point is 12F. (-11C).
  • Possesses a faint ammonia odor.
  • Has no flames
  • Is not colored
  • Is non-polluting and non-toxic
  • Is safe to handle, although some metals may be corroded by it
  • Many gas stations have it readily available at the pump, or you may buy it in containers.
  • The color blue is frequently used as an identifier in filler caps and merchandise. (The fill cap for TITAN XD Diesel DEF is blue.)

Various other names for DEF

  • Urea
  • AUS 32 (Aqueous Urea Solution 32)
  • AdBlue
  • Agent for Reducing NOx
  • Activator Solution

NOTE: The Electronic Service Manual (ESM) and CONSULT-III plus may refer to DEF as Reductant or Urea.

  • Diesel Exhaust Fluid (DEF) is stored in the DEF tank, which contains 4.5 US gallons (17 L), and needs to be renewed when the DEF level display indicates that there is insufficient DEF.
  • Based on factors that affect how the vehicle is used, such as driving conditions, loads, speeds,
  • Nissan advises using a DEF that complies with ISO 22241 standards.
  • DEF can be kept in sealed containers out of the sun for up to 18 months at temperatures between -5C and 23C (23F and 77F). However, the shelf life is shortened by 6 months for every 9F (5C) increase above this advised range.
  • Additionally, unused vehicles’ DEF tanks shouldn’t be left full for longer than six months.
  • DEF should never be mixed with water. Watering down DEF will alter its concentration, which will lessen the efficiency of SCR. The DEF dosing valve may potentially become corroded or damaged by chemicals introduced by adding unpurified water. Additionally, DEF’s freezing point will rise if water is added.
  • A refractometer that has been calibrated for DEF can be used to measure DEF concentration.
  • Behind the fuel tank, the DEF tank is positioned underneath the car. DEF is injected into the tank using a

The following parts of the DEF system are housed in the DEF tank:

  • The ECM and the DEF control unit converse and exchange data. The control unit regulates the operation of the DEF pump assembly, including the DEF heating systems, using inputs from the ECM and other sensors.
  • On the side of the DEF tank is a sensor for measuring DEF quality. This sensor measures the amount of urea in the DEF to determine whether it is appropriate for successful dosage (approximately 32.5 percent Urea). A message reading DEF System Error – SEE Dealer will appear on the Vehicle Information Display in the combination meter if the DEF quality sensor detects a wrong DEF concentration.

NOTE: The aftertreatment system will not function properly if the DEF tank is filled with anything other than DEF or with diluted DEF. Engine power reductions come once a DTC is set.

  • The DEF pump assembly is attached to the tank’s bottom, and the majority of it is immersed in DEF inside the tank.

What’s in the pump assembly?

  • Fuel Pump The pump pulls DEF through its suction port, pressurizes, filters, and then sends it through the pressure outlet port and dosing line to the DEF dosing valve.
  • Heater for DEF tanks
  • The frozen DEF in the tank is thawed using the heater for the DEF tank. The DEF tank heater is made up of several heated strips that work together to gradually defrost frozen DEF.
  • Temperature sensor for DEF
  • This sensor data is used by the DEF control unit to determine whether tank heater activity is required.
  • Sensor for DEF Level
  • The DEF control unit and the ECM receive information from this sensor about the amount of DEF in the DEF tank. This sensor data is also used by the combination meter’s DEF level display.
  • Pressure Sensor for DEF
  • To ensure that there is sufficient pressure available for DEF dosing, this sensor continuously checks the pressure in the DEF dosing line. In order to make sure DEF has been removed from the line after the ignition has been switched OFF, the DEF pressure sensor additionally keeps track of the line pressure.
  • DEF Dosing Line HeaterA DEF dosing line heater is situated where the DEF dosing line connects to the DEF pump at the end of the DEF dosing line. In order to prevent freezing while driving, this heater is utilized to heat the dosing line that runs between the DEF pump and the DEF dosing valve.
  • Connector Line For DEF
  • The DEF connection line transports DEF from the DEF tank back to the DEF tank during system purging. It also transports DEF to the dosing valve during dosing operation.
  • Valve for Dosing
  • The decomposing tube contains the DEF dosing valve. When the ECM instructs it to do so, the Pulse Width Modulation (PWM) valve emits a fine mist of DEF into the exhaust stream. Due to the fact that the SCR catalyst employs DEF to chemically change NOx into nitrogen and water, this DEF spray is frequently referred to as SCR dosing.
  • Since DEF freezes at 12F (-11C), the DEF control unit uses the DEF temperature sensor to determine whether DEF tank heating is necessary when the ignition is turned on. The DEF must be sufficiently warmed before the DEF control unit will instruct the pump to prime. If necessary, DEF heating will turn on and keep heating the DEF in accordance with the thawing time schedule.
  • In addition, the DEF system contains heaters in both the pump and the DEF dosing line. The DEF control unit will additionally activate these heaters in accordance with the ambient temperature in order to defrost frozen DEF prior to priming and to stop DEF from freezing while the vehicle is in operation.
  • The Selective Catalytic Reduction starts to heat up after the engine starts (SCR). The DEF control unit will instruct the DEF pump to begin its priming operation when the SCR reaches 302F (150C) and the DEF temperature is within acceptable limits. After being pressurized, filtered, and sent through the DEF dosing line to the DEF dosing valve, the DEF pump draws DEF from the tank. The DEF dosing valve is instructed to open and close by the ECM in order to remove any air from the system. When the system reaches the necessary pressure, it is prepared to dose (dosing state).
  • When the system is in the dosing condition, the DEF pump runs constantly to maintain the pressure in the DEF dosing line. Whether the dosing valve is spraying DEF or not, the pump keeps running.
  • The ECM has direct control over the DEF dosing valve. When the ECM decides that DEF dosing is necessary, it activates the DEF dosing valve with a PWM signal, spraying DEF into the decomposition tube. The ECM issues directions for dosing frequency and quantity dependent on a number of sensor inputs and engine running circumstances, therefore dosing is not always consistent.
  • Effective dosing needs to take place under the following circumstances:

Both the SCR outlet temperature and the SCR intake temperature must be at least 392F (150C) (200C)

NOTE: To assess if the aftertreatment system is effectively eliminating NOx, the ECM compares the values of the NOx sensors at the intake and output. If NOx levels at the outlet NOx sensor continue to be too high, the ECM may order more EGR or more DEF dosage to bring them down.

  • The DEF system starts purging when the engine and ignition are shut off. The DEF pump assembly produces an audible click and a pumping sound while it is in a purge cycle. The internal reversing valve of the DEF pump will slide, changing the DEF’s flow direction. The DEF pump empties the fluid tank of any remaining DEF after removing all of it from the fluid dosing valve and line. The DEF dosing valve opens during the purging procedure, removing any vacuum that might have been formed in the line and enabling a more thorough purge.
  • When the DEF lines are not in use, they should be purged or removed to prevent damage from freezing in cold areas.
  • A DTC will be set if power to the DEF control unit is interrupted, such as by unplugging the battery before the purging procedure is finished. In CONSULT-III plus, you may see the incomplete purge counter.

Along with DEF warning signals in the vehicle information display, the instrument cluster has a DEF warning bulb. There won’t be any warnings if the DEF level is between 25 and 100 percent full. Warnings will show system status and describe performance decline as follows if the DEF level is below 25%: