Error Code P20B8: What It Means & What To Do?

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Do you know what the P20B8 error code means? How can this error be solved? What are its symptoms and diagnosis? Are you looking for an answer to these questions? Then read further to know more. The P20B8 error code which relates to the electrical wiring issue is known as the reductant unit heater control circuit performance. The DEF fluid is looked after by the reductant DEF system which is a heating unit and makes sure that it does not freeze or crystallize in between the tank and the injector. The P20B8 error code will get stored in the vehicle if the heating unit does not function as expected.

As you turn the key on, does the fuel pump not primp at times? Then you must start inspecting the fuel pressure and also see if there are any bright white-bluish spark at the corner of all the four plugs. Additionally, you must also visually inspect and carefully check the mechanical timing which is as mentioned above.

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

• The improper functioning of the reductant metering unit heater control.
• You might find the harness of the reductant metering unit heater control to be opened or the circuit might be shorted.
• The electrical connection might be bad in the reductant metering unit heater control.

1. Reductant Metering Unit Heater - The broken or damaged reductant metering unit heater needs quick replacement to avoid P20B8 error code.
2. Diesel Exhaust Fluid System - The check engine light will start flashing or illuminating if the DEF system is damaged. Replace the defective DEF system as soon as possible.
3. Diesel Exhaust Fluid - The SCR system in the vehicle will shut down which in turn shutdowns the engine. Avoid the P20B8 error getting stored in the vehicle by changing the dirty DEF.
4. Heater Module - The heater will fail to produce warm air if the heater module is defective. Replace it as soon as possible.
5. Heater Module Switch - A faulty or broken heater control switch needs immediate replacement so that the P20B8 error can be avoided in the vehicle.
6. Powertrain Control Module - You can find the powertrain control module to be damaged if the engine light keeps flashing and if the car fails to start immediately. The right replacement for your damaged powertrain control module can be found at Parts Avatar.

Our main motive is to achieve customer satisfaction and that’s why we will help you to diagnose P20B8 code by mentioning some major symptoms below:

Common Symptoms

• An impossible condition for the DPF regeneration to occur.
• You will see a warning light from the service engine or the engine light may be on.

Have a look at some ways with which you can correct the P20B8 code:

• The reductant metering unit heater controls harness and the circuit which is defective needs a quick replacement.
• Changing the broken reductant metering unit heater control.
• The poor diesel exhaust fluid needs a quick replacement.
• The broken heater module switch has to be fixed.

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 reductant metering unit heater, DEF system, DEF fluid, DEF diesel, DEF fuel, power module, power control module, module heater, heater module, heater module switch and many more. Now all your problems would vanish within no time.

This code is related to P20B5, P20B6, and P20B7.

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

It is essential to diagnose this fault code. Here are some steps which a mechanic should follow for diagnosing the problem that triggered a P20B8 code to be stored:

• This is a usual type of diagnostic trouble code where a scanner will be used by the mechanic or the trained professional to determine the error code that is stored in the vehicle.
• The freeze frame data and stored codes in the vehicle will be recovered with the help of a scanner when it is connected to the diagnostic port of the vehicle.
• This information can help the trained professional to proceed further with the diagnostic process.
• As a very first step, the mechanic will start checking the reductant metering unit heater control and see if there are any faults or defects in the systems
• If he comes across any damages or defects, it will be instantly fixed.
• If the mechanic does not find any faults or defects, he will then start inspecting the harness of the reductant metering unit heater control if there are any openings or short circuit.
• Also, the electrical connection will be inspected to know if it is weak. If the electrical connection is weak, the issue will be immediately addressed.
• Very rarely, the mechanic may find the powertrain control module to be defective or damaged. The mechanic will fix this issue as needed.
• Once the diagnostic procedure is carefully done, the mechanic will reset the code, test drive the vehicle and see if the error code still appears in the vehicle.
• This process is usually carried out to help the technician to know as to where the error code was stored in the vehicle.

Common Mistakes When Diagnosing the P20B8 Code

• The wires might cause some issue.
• Malfunctioning of the delivery module heater.
• Power heater module power switch might be faulty.