How severe is this DTC?

A stored P20BB code should be considered severe and addressed as soon as possible. The SCR system may be disabled because of this. Catalyst damage could occur if the conditions that contributed to the code being stored are not corrected in a timely manner.

What are some symptoms of the code?

Symptoms of a P20BB fault code may include:

• Decreased engine performance
• Excessive black smoke from the vehicle’s exhaust
• Reduced fuel efficiency
• Other SCR-related codes

What are some common causes of the code?

Causes

of this code may include:

• Faulty reductant heater
• Open or shorted circuits in the reductant heater control
• Defective reductant temperature sensor
• Faulty SCR controller/PCM or programming error

What are the troubleshooting steps for P20BB?

You will need access to a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a source of vehicle-specific diagnostic information to diagnose a P20BB code.

If you can find a technical service bulletin (TSB) that matches the vehicle’s year, make, and model; as well as the engine size, stored code(s), and presented symptoms, it could provide helpful diagnostic information.

You’ll want to start your diagnosis with a visual inspection of the reductant heater system harnesses and connectors. Burned or damaged wiring and/or connectors should be repaired or replaced before continuing.

Proceed by connecting the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and relevant freeze frame data. Note this information before clearing the codes and test drive the vehicle until the PCM enters readiness mode or the code resets.

The code is intermittent and may be much harder to diagnose (for now), if the PCM enters readiness mode. If this is the case, the conditions that contributed to the code being stored may need to worsen before an accurate diagnosis can be made.

If the code resets, consult your vehicle information source for diagnostic flowcharts, connector pinout diagrams, connector face views, as well as component testing procedures and specifications. This information will be needed to complete the next step of your diagnosis.

Use the DVOM to test the SCR/control system power supply. Test fuses with the circuit loaded to avoid misdiagnosis. If proper power (battery voltage) and ground circuits are found, use the scanner to activate the reductant heater(s) and test the output control circuit voltage. If voltage is insufficient, suspect the controller is faulty or has encountered a programming error.

If the output voltage circuit is within parameters, use the DVOM to test the reductant heater element in question. If the heater does not meet manufacturer specifications, suspect it has failed.

If this code is displayed in warm weather, suspect a programming error has occurred.

How severe is this DTC?

A stored P20BC code should be considered severe and addressed as soon as possible. The SCR system may be disabled because of this. Catalyst damage could occur if the conditions that contributed to the code being stored are not corrected in a timely manner.

What are some of the symptoms of the code?

Symptoms of a P20BC trouble code may include:

• Decreased engine performance
• Excessive black smoke from the vehicle’s exhaust
• Reduced fuel efficiency
• Other SCR-related codes

What are some common causes of the code?

Causes

of this code may include:

• Faulty reductant heater
• Open or shorted circuits in the reductant heater control
• Defective reductant temperature sensor
• Faulty SCR controller/PCM or programming error

What are the troubleshooting steps for P20BC?

You will need access to a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a source of vehicle-specific diagnostic information to diagnose a P20BC code.

If you can find a Technical Service Bulletin (TSB) that matches the vehicle’s year, make, and model; as well as the engine size, stored code(s), and presented symptoms, it could provide helpful diagnostic information.

You’ll want to start your diagnosis with a visual inspection of the reductant heater system’s wiring harnesses and connectors. Burned or damaged wiring and/or connectors should be repaired or replaced before continuing.

Proceed by connecting the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and relevant freeze frame data. Note this information before clearing the codes and test drive the vehicle until the PCM enters readiness mode or the code resets.

The code is intermittent and may be much harder to diagnose (for now), if the PCM enters readiness mode. If this is the case, the conditions that contributed to the code being stored may need to worsen before an accurate diagnosis can be made.

If the code resets, consult your vehicle information source for diagnostic flowcharts, connector pinout diagrams, connector face views, as well as component testing procedures and specifications. This information will be needed to complete the next step of your diagnosis.

Use the DVOM to test the SCR control system’s power supply. Test fuses with the circuit loaded to avoid misdiagnosis. If proper power (battery voltage) and ground circuits are found, use the scanner to activate the reductant heater(s) and test the output control circuit voltage. If the voltage is insufficient, suspect a faulty controller or a programming error.

If the output voltage circuit is within parameters, use the DVOM to test the reductant heater in question. If the heater does not meet the manufacturer’s specifications, suspect it has failed.

If this code is displayed in warm weather, suspect that a programming error has occurred.

How severe is this DTC?

A stored P20BD code should be considered severe and addressed as soon as possible. The SCR system may be disabled because of this. Catalyst damage could occur if the conditions that contributed to the code being stored are not corrected in a timely manner.

What are some of the symptoms of the code?

Symptoms of a P20BD fault code may include:

• Decreased engine performance
• Excessive black smoke from the vehicle’s exhaust
• Reduced fuel efficiency
• Other SCR-related codes

What are some common causes of the code?

Causes

of this code may include:

• Faulty reductant heater
• Open or shorted circuits in the reductant heater control
• Defective reductant temperature sensor
• Faulty SCR controller/PCM or programming error

What are the troubleshooting steps for P20BD?

You will need access to a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a source of vehicle-specific diagnostic information to diagnose a P20BD code.

If you can find a technical service bulletin (TSB) that matches the vehicle’s year, make, and model; as well as the engine size, stored code(s), and presented symptoms, it could provide helpful diagnostic information.

You’ll want to start your diagnosis with a visual inspection of the reductant heater system harnesses and connectors. Burned or damaged wiring and/or connectors should be repaired or replaced before continuing.

Proceed by hooking up the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and relevant freeze frame data. Note this information before clearing the codes and test drive the vehicle until the PCM enters readiness mode or the code resets.

The code is intermittent and may be much more difficult to diagnose (for the time being) if the PCM enters readiness mode. If this is the case, the conditions that contributed to the code being stored may need to worsen before an accurate diagnosis can be made.

If the code resets, consult your vehicle information source for diagnostic flowcharts, connector pinout diagrams, connector face views, as well as component testing procedures and specifications. This information will be needed to complete the next step of your diagnosis.

Use the DVOM to test the SCR control system’s power supply. Test fuses with the circuit loaded to avoid misdiagnosis. If proper power (battery voltage) and ground circuits are found, use the scanner to activate the reductant heater(s) and test the output control circuit voltage. If voltage is insufficient, suspect the controller is faulty or has encountered a programming error.

If the output voltage circuit is within parameters, use the DVOM to test the reductant heater element in question. If the heater does not meet manufacturer specifications, suspect it has failed.

If this code is displayed during warm weather, suspect a programming error has occurred

How severe is this DTC?

A stored P20BE code should be considered severe and addressed as soon as possible. The SCR system may be disabled because of this. Catalyst damage could occur if the conditions that contributed to the code being stored are not corrected in a timely manner.

What are some of the symptoms of the code?

Symptoms of a P20BE fault code may include:

• Decreased engine performance
• Excessive black smoke from the vehicle’s exhaust
• Reduced fuel efficiency
• Other SCR-related codes

What are some common causes of the code?

Causes

of this code may include:

• Faulty reductant heater
• Open or shorted circuits in the reductant heater control
• Defective reductant temperature sensor
• Faulty SCR controller/PCM or programming error

What are the troubleshooting steps for P20BE?

You will need access to a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a source of vehicle-specific diagnostic information to diagnose a P20BE code.

If you can find a Technical Service Bulletin (TSB) that matches the vehicle’s year, make, and model; as well as the engine size, stored code(s), and presented symptoms, it could provide helpful diagnostic information.

You’ll want to start your diagnosis with a visual inspection of the reductant heater system’s wiring harnesses and connectors. Burned or damaged wiring and/or connectors should be repaired or replaced before continuing.

Proceed by connecting the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and relevant freeze frame data. Note this information before clearing the codes and test drive the vehicle until the PCM enters readiness mode or the code resets.

The code is intermittent and may be much harder to diagnose (for the time being) if the PCM enters readiness mode. If this is the case, the conditions that contributed to the code being stored may need to worsen before an accurate diagnosis can be made.

If the code resets, consult your vehicle information source for diagnostic flowcharts, connector pinout diagrams, connector face views, as well as component testing procedures and specifications. This information will be needed to complete the next step of your diagnosis.

Use the DVOM to test the SCR control system’s power supply. Test fuses with the circuit loaded to avoid misdiagnosis. If proper power (battery voltage) and ground circuits are found, use the scanner to activate the reductant heater(s) and test the output control circuit voltage. If the voltage is insufficient, suspect a faulty controller or a programming error.

If the output voltage circuit is within parameters, use the DVOM to test the reductant heater in question. If the heater does not meet manufacturer specifications, suspect it has failed.

If this code is displayed in warm weather, suspect a programming error has occurred.

How severe is this DTC?

A stored P20BF code should be considered severe and addressed as soon as possible. The SCR system could be disabled because of this. Catalyst damage could occur if the conditions that contributed to the code being stored are not corrected in a timely manner.

What are some of the symptoms of the code?

Symptoms of a P20BF trouble code may include:

• Decreased engine performance
• Excessive black smoke from the vehicle’s exhaust
• Reduced fuel efficiency
• Other SCR-related codes

What are some common causes of the code?

Causes of this code may include:

• Faulty reductant heater
• Open or shorted circuits in the reductant heater control
• Defective reductant temperature sensor
• Faulty SCR controller/PCM or programming error

What are the troubleshooting steps for P20BF?

You will need access to a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a source of vehicle-specific diagnostic information to diagnose a P20BF code.

If you can find a technical service bulletin (TSB) that matches the vehicle’s year, make, and model; as well as the engine size, stored code(s), and presented symptoms, it could provide useful diagnostic information.

You’ll want to start your diagnosis with a visual inspection of the reductant heater system harnesses and connectors. Burned or damaged wiring and/or connectors should be repaired or replaced before continuing.

Proceed by connecting the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and relevant freeze frame data. Note this information before clearing the codes and test drive the vehicle until the PCM enters readiness mode or the code resets.

The code is intermittent and may be much more difficult to diagnose (for the time being) if the PCM enters readiness mode. If this is the case, the conditions that contributed to the code being stored may need to worsen before an accurate diagnosis can be made.

If the code resets, consult your vehicle information source for diagnostic flowcharts, connector pinout diagrams, connector face views, as well as component testing procedures and specifications. This information will be needed to complete the next step of your diagnosis.

Use the DVOM to test the SCR control system’s power supply. Test fuses with the circuit loaded to avoid misdiagnosis. If proper power (battery voltage) and ground circuits are found, use the scanner to activate the reductant heater(s) and test the output control circuit voltage. If voltage is insufficient, suspect a faulty controller or a programming error.

If the output voltage circuit is within parameters, use the DVOM to test the reductant heater in question. If the heater does not meet manufacturer specifications, suspect it has failed.

If this code appears in warm weather, suspect a programming error has occurred.

How serious is this DTC?

A stored P20C0 code should be considered serious and addressed as soon as possible. The SCR system may be disabled because of this. Catalyst damage could occur if the conditions that contributed to the code being stored are not corrected in a timely manner.

What are some of the symptoms of the code?

Symptoms of a P20C0 fault code may include:

• Decreased engine performance
• Excessive black smoke from the vehicle’s exhaust
• Reduced fuel efficiency
• Other SCR-related codes

What are some common causes of the code?

Causes

of this code may include:

• Faulty reductant heater
• Open or shorted circuits in the reductant heater control
• Defective reductant temperature sensor
• Faulty SCR controller/PCM or programming error

What are the troubleshooting steps for P20C0?

You will need access to a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a source of vehicle-specific diagnostic information to diagnose a P20C0 code.

If you can find a Technical Service Bulletin (TSB) that matches the vehicle’s year, make, and model; as well as the engine size, stored code(s), and presented symptoms, it could provide helpful diagnostic information.

You will want to start your diagnosis with a visual inspection of the reductant heater system’s wiring harnesses and connectors. Burned or damaged wiring and/or connectors should be repaired or replaced before continuing.

Proceed by connecting the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and relevant freeze frame data. Note this information before clearing the codes and test drive the vehicle until the PCM enters readiness mode or the code resets.

The code is intermittent and may be much more difficult to diagnose (for the time being) if the PCM enters readiness mode. If this is the case, the conditions that contributed to the code being stored may need to worsen before an accurate diagnosis can be made.

If the code resets, consult your vehicle information source for diagnostic flowcharts, connector pinout diagrams, connector face views, as well as component testing procedures and specifications. This information will be needed to complete the next step of your diagnosis.

Use the DVOM to test the SCR/control system’s power supply. Test fuses with the circuit loaded to avoid a misdiagnosis. If the proper power (battery voltage) and ground circuits are found, use the scanner to activate the reductant heater(s) and test the output control circuit voltage. If the voltage is insufficient, suspect that the controller is faulty or has encountered a programming error.

If the output voltage circuit is within parameters, use the DVOM to test the reductant heater element in question. If the heater does not meet the manufacturer’s specifications, suspect that it has failed.

If this code is displayed in warm weather, suspect that a programming error has occurred.

How serious is this DTC?

A stored P20C1 code should be considered serious and addressed as soon as possible. The SCR system could be disabled because of this. Catalyst damage could occur if the conditions that contributed to the code being stored are not corrected in a timely manner.

What are some of the symptoms of the code?

Symptoms of a P20C1 fault code may include:

• Decreased engine performance
• Excessive black smoke from the vehicle’s exhaust
• Reduced fuel efficiency
• Other SCR-related codes

What are some common causes of the code?

Causes of this code may include:

• Faulty reductant heater
• Open or shorted circuits in the reductant heater control
• Defective reductant temperature sensor
• Faulty SCR controller/PCM or programming error

What are the troubleshooting steps for P20C1?

You will need access to a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a source of vehicle-specific diagnostic information to diagnose a P20C1 code.

If you can find a technical service bulletin (TSB) that matches the vehicle’s year, make, and model; as well as the engine size, stored code(s), and presented symptoms, it could provide useful diagnostic information.

You’ll want to start your diagnosis with a visual inspection of the reductant heater system’s wiring harnesses and connectors. Burned or damaged wiring and/or connectors should be repaired or replaced before continuing.

Proceed by connecting the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and relevant freeze frame data. Note this information before clearing the codes and test drive the vehicle until the PCM enters readiness mode or the code resets.

The code is intermittent and may be much more difficult to diagnose (for the time being) if the PCM enters readiness mode. If this is the case, the conditions that contributed to the code being stored may need to worsen before an accurate diagnosis can be made.

If the code resets, consult your vehicle information source for diagnostic flowcharts, connector pinout diagrams, connector face views, as well as component testing procedures and specifications. This information will be needed to complete the next step of your diagnosis.

Use the DVOM to test the SCR control system’s power supply. Test fuses with the circuit loaded to avoid misdiagnosis. If proper power (battery voltage) and ground circuits are found, use the scanner to activate the reductant heater(s) and test the output control circuit voltage. If the voltage is insufficient, suspect that the controller is faulty or has encountered a programming error.

If the output voltage circuit is within parameters, use the DVOM to test the reductant heater in question. If the heater does not meet the manufacturer’s specifications, suspect that it has failed.

If this code is displayed in warm weather, suspect that a programming error has occurred…

How serious is this DTC?

A stored P20C2 code should be considered serious and addressed as soon as possible. The SCR system may be disabled because of this. Catalyst damage could occur if the conditions that contributed to the code being stored are not corrected in a timely manner.

What are some of the symptoms of the code?

Symptoms of a P20C2 fault code may include:

• Decreased engine performance
• Excessive black smoke from the vehicle’s exhaust
• Reduced fuel efficiency
• Other SCR-related codes

What are some common causes of the code?

Causes

of this code may include:

• Faulty reductant heater
• Open or shorted circuits in the reductant heater control
• Defective reductant temperature sensor
• Faulty SCR controller/PCM or programming error

What are the troubleshooting steps for P20C2?

You will need access to a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a source of vehicle-specific diagnostic information to diagnose a P20C2 code.

If you can find a technical service bulletin (TSB) that matches the vehicle’s year, make, and model; as well as the engine size, stored code(s), and presented symptoms, it could provide helpful diagnostic information.

You’ll want to start your diagnosis with a visual inspection of the reductant heater system’s wiring harnesses and connectors. Burned or damaged wiring and/or connectors should be repaired or replaced before continuing.

Proceed by connecting the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and relevant freeze frame data. Note this information before clearing the codes and test drive the vehicle until the PCM enters readiness mode or the code resets.

The code is intermittent and may be much harder to diagnose (for the time being) if the PCM enters readiness mode. If this is the case, the conditions that contributed to the code being stored may need to worsen before an accurate diagnosis can be made.

If the code resets, consult your vehicle information source for diagnostic flowcharts, connector pinout diagrams, connector face views, as well as component testing procedures and specifications. This information will be needed to complete the next step of your diagnosis.

Use the DVOM to test the SCR/control system’s power supply. Test fuses with the circuit loaded to avoid misdiagnosis. If proper power (battery voltage) and ground circuits are found, use the scanner to activate the reductant heater(s) and test the output control circuit voltage. If voltage is insufficient, suspect the controller is faulty or has encountered a programming error.

If the output voltage circuit is within parameters, use the DVOM to test the reductant heater element in question. If the heater does not meet manufacturer specifications, suspect it has failed.

If this code is displayed in warm weather, suspect a programming error has occurred

How severe is this DTC?

A stored P20C3 code should be considered severe and addressed as quickly as possible. The SCR system could be disabled because of this. Catalyst damage could occur if the conditions that contributed to the code being stored are not corrected in a timely manner.

What are some of the symptoms of the code?

Symptoms of a P20C3 trouble code may include:

• Decreased engine performance
• Excessive black smoke from vehicle exhaust
• Reduced fuel efficiency
• Other SCR-related codes

What are some common causes of the code?

Causes

of this code may include:

• Faulty reductant heater
• Open or shorted circuits in reductant heater control
• Defective reductant temperature sensor
• Faulty SCR controller/PCM or programming error

What are the troubleshooting steps for P20C3?

You will need access to a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a source of vehicle-specific diagnostic information to diagnose a P20C3 code.

If you can find a technical service bulletin (TSB) that matches the vehicle’s year, make, and model; as well as engine size, stored code(s), and presented symptoms, it could provide helpful diagnostic information.

You’ll want to start your diagnosis with a visual inspection of the reductant heater system harnesses and connectors. Burned or damaged wiring and/or connectors should be repaired or replaced before continuing.

Proceed by hooking up the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and relevant freeze frame data. Note this information before clearing the codes and test drive the vehicle until the PCM enters readiness mode or the code resets.

The code is intermittent and may be much harder to diagnose (for now), if the PCM enters readiness mode. If this is the case, the conditions that contributed to the code being stored may need to worsen before an accurate diagnosis can be made.

If the code resets, consult your vehicle information source for diagnostic flowcharts, connector pinout diagrams, connector face views, as well as component testing procedures and specifications. This information will be needed to complete the next step of your diagnosis.

Use the DVOM to test the SCR/control system power supply. Test fuses with the circuit loaded to avoid misdiagnosis. If proper power (battery voltage) and ground circuits are found, use the scanner to activate the reductant heater(s) and test the output control circuit voltage. If voltage is insufficient, suspect the controller is faulty or encountered a programming error.

If the voltage output circuit is within parameters, use the DVOM to test the reductant heater element in question. If the heater does not meet manufacturer specifications, suspect it has failed.

If this code is displayed in warm weather, suspect a programming error has occurred

How severe is this DTC?

A stored P20C4 code should be considered severe and addressed as soon as possible. The SCR system could be disabled because of this. Catalyst damage could occur if the conditions that contributed to the code being stored are not corrected in a timely manner.

What are some of the symptoms of the code?

Symptoms of a P20C4 trouble code may include:

• Decreased engine performance
• Excessive black smoke from the vehicle’s exhaust
• Reduced fuel efficiency
• Other SCR-related codes

What are some common causes of the code?

Causes of this code may include:

• Faulty reductant heater
• Open or shorted circuits in the reductant heater control
• Defective reductant temperature sensor
• Faulty SCR controller/PCM or programming error

What are the troubleshooting steps for P20C4?

You will need access to a diagnostic scanner, a digital volt/ohmmeter (DVOM), and a source of vehicle-specific diagnostic information to diagnose a P20C4 code.

If you can find a technical service bulletin (TSB) that matches the vehicle’s year, make, and model; as well as the engine size, stored code(s), and presented symptoms, it could provide helpful diagnostic information.

You’ll want to start your diagnosis with a visual inspection of the reductant heater system’s wiring harnesses and connectors. Burned or damaged wiring and/or connectors should be repaired or replaced before continuing.

Proceed by connecting the scanner to the vehicle’s diagnostic connector and retrieving all stored codes and relevant freeze frame data. Note this information before clearing the codes and test drive the vehicle until the PCM enters readiness mode or the code resets.

The code is intermittent and may be much more difficult to diagnose (for the time being) if the PCM enters readiness mode. If this is the case, the conditions that contributed to the code being stored may need to worsen before an accurate diagnosis can be made.

If the code resets, consult your vehicle information source for diagnostic flowcharts, connector pinout diagrams, connector face views, as well as component testing procedures and specifications. This information will be needed to complete the next step of your diagnosis.

Use the DVOM to test the SCR control system’s power supply. Test fuses with the circuit loaded to avoid misdiagnosis. If proper power (battery voltage) and ground circuits are found, use the scanner to activate the reductant heater(s) and test the output control circuit voltage. If voltage is insufficient, suspect the controller is faulty or has encountered a programming error.

If the output voltage circuit is within parameters, use the DVOM to test the reductant heater element in question. If the heater does not meet manufacturer specifications, suspect it has failed.

If this code is displayed in warm weather, suspect a programming error has occurred.