What does P202F Reductant/Regeneration Supply Control Circuit Range/Performance mean?
The P202F diagnostic trouble code (DTC) is a generic powertrain code that may occur in many OBD-II vehicles.
When this code is stored, it means that the powertrain control module (PCM) has detected insufficient activity in the control circuit for the reductant/regeneration supply pump.
This pump is responsible for pressurizing a reductant compound or diesel exhaust fluid (DEF) that is injected into the exhaust system to optimize pollutant filtration and reduce harmful emissions.
This code should be considered severe and addressed promptly, as it could potentially disable the selective catalytic reduction (SCR) system and cause catalyst damage.
Symptoms may include reduced fuel efficiency, excessive black smoke from the exhaust, diminished engine performance, and other SCR-related codes.
Possible causes for this code include a defective reductant supply pump, open or shorted circuits in the control system, or a malfunctioning SCR controller/PCM.
Diagnosing and troubleshooting this code will require a diagnostic scanner, a digital voltmeter (DVOM), and access to vehicle-specific diagnostic information.
P202F Symptoms
- Reduction in fuel efficiency
- Excessive black smoke from vehicle exhaust
- Diminished engine performance
- Other SCR related codes
Possible P202F Causes
- Defective reductant supply pump (overload)
- Open or shorted circuits in the reductant supply control
- Bad SCR controller/PCM or programming error
Troubleshooting P202F error code
- Use a diagnostic scanner to retrieve all stored codes and freeze frame data
- Clear the codes and test-drive the vehicle until the PCM enters readiness mode or the code is reset
- If the code is intermittent, worsen the conditions that contributed to the code being stored
- Search for diagnostic flow-charts, connector pin-out charts, connector face views, and component testing procedures/specifications
- Use a digital volt/ohmmeter (DVOM) to test the reductant tank supply pump according to manufacturer specifications
- Test reductant supply pump voltage with the pump activated
- Test input and output signal circuits from the fuse panel, PCM, and ignition switch using the DVOM