P202F – Reductant Tank Temperature Sensor Circuit Range/Performance
POSTED IN pcodes
Updated on:
Urgency Assessment
The P202F diagnostic trouble code (DTC) is considered severe and should be addressed promptly. While it may not require immediate vehicle shutdown, prolonged driving with this issue can lead to:
In our workshop, we've encountered the P202F code across various European car makes, with Mercedes-Benz, BMW, and Audi being the most frequent offenders. We've noticed this code often appears in diesel models equipped with Selective Catalytic Reduction (SCR) systems. From our experience, the issue is typically related to the reductant supply pump or its control circuit. In Mercedes vehicles, we've found that faulty DEF (Diesel Exhaust Fluid) pumps are a common culprit, while BMWs often suffer from wiring issues in the SCR system. Audis, on the other hand, tend to have problems with the DEF quality sensor. Interestingly, we've seen fewer instances of this code in American or Asian vehicles, suggesting that European manufacturers may be more prone to this particular issue, possibly due to their more complex emissions control systems.
- Reduced fuel efficiency
- Excessive black smoke from the exhaust
- Diminished engine performance
- Potential damage to the catalytic converter
It is recommended to have the vehicle inspected by a qualified technician as soon as possible. If symptoms worsen, consider limiting driving until the issue is resolved.
Detailed Code Information
P202F is a generic powertrain code applicable to OBD-II vehicles (1996 and newer). It indicates that the powertrain control module (PCM) has detected an issue with the reductant/regeneration supply control circuit's range or performance.
While generic, the specific repair steps may vary depending on the vehicle's make, model, and year. This code is commonly found in diesel engines equipped with Selective Catalytic Reduction (SCR) systems.
Buy tested tuning file for Adblue / EGR / DPF / Adblue off now!
Register Now or Already have an account, Login now
Components Involved
The P202F code primarily involves the SCR system, which is crucial for reducing NOx emissions in diesel engines. Key components include:
- Reductant/regeneration supply pump
- Diesel Exhaust Fluid (DEF) injector
- DEF tank and lines
- Pressure and temperature sensors
- PCM or dedicated SCR controller
The reductant supply pump pressurizes the DEF for injection into the exhaust stream. The PCM monitors the pump's voltage and load percentage, as well as system pressure, to ensure proper operation.
Common Causes
- Defective reductant supply pump (most common)
- Open or shorted circuits in the reductant supply control
- Faulty PCM or SCR controller
- Clogged or damaged DEF injector
- Contaminated or incorrect DEF fluid
- Leaks in the DEF system
- Faulty pressure or temperature sensors
Diagnostic Procedure
- Connect an OBD-II scanner and verify the P202F code
- Check for additional related codes
- Review freeze frame data for conditions when the code was set
- Inspect DEF fluid level and quality
- Visually inspect DEF system components for damage or leaks
- Test the reductant supply pump using a digital multimeter (DVOM):
- Measure resistance (typical range: 1-5 ohms)
- Check voltage (should be close to battery voltage when activated)
- Inspect wiring and connectors for damage or corrosion
- Test pressure and temperature sensors
- Use a scan tool to manually activate the pump and monitor system pressure
Required tools: OBD-II scanner, DVOM, manufacturer-specific diagnostic information
Solutions
- Replace faulty reductant supply pump
- Repair or replace damaged wiring and connectors
- Clean or replace clogged DEF injector
- Refill or replace contaminated DEF fluid
- Replace faulty sensors
- In rare cases, replace PCM or SCR controller
Prevention
- Use high-quality DEF fluid and maintain proper levels
- Regularly inspect DEF system components for leaks or damage
- Follow manufacturer-recommended maintenance schedules
- Address any DEF-related warning lights promptly
Cost Analysis
Estimated repair costs (USD/EUR):
- Reductant supply pump replacement: $300-$800 / €250-€675
- DEF injector replacement: $200-$500 / €170-€425
- Wiring repairs: $100-$300 / €85-€250
- PCM replacement (rare): $500-$1500 / €425-€1275
Labor costs vary by region and shop rates.
DIY Repair Guide
For skilled mechanics:
- Ensure proper safety equipment (gloves, eye protection)
- Disconnect the battery
- Locate the reductant supply pump (typically near the DEF tank)
- Disconnect electrical connections and DEF lines
- Remove mounting bolts and extract the pump
- Install the new pump, ensuring proper alignment
- Reconnect DEF lines and electrical connections
- Refill DEF tank if necessary
- Clear DTCs and perform a system test
Related Issues
P202F may coincide with other SCR-related codes such as:
- P20EE (SCR NOx Catalyst Efficiency Below Threshold)
- P204F (Reductant System Performance)
- P203F (Reductant Level Sensor Circuit Range/Performance)
Always perform a comprehensive scan to identify all related issues.
Technical Specifications
- DEF pump pressure: Typically 4.5-5.5 bar (65-80 psi)
- DEF injection temperature range: -11°C to 32°C (12°F to 90°F)
- Typical DEF consumption: 2-3% of fuel consumption rate
By addressing P202F promptly and thoroughly, engineers and mechanics can ensure optimal performance of the SCR system, maintaining both engine efficiency and environmental compliance.
Frequently Asked Questions About P202F
What does the P202F code mean?
P202F stands for “Reductant/Regeneration Supply Control Circuit Range/Performance.” It indicates an issue with the control circuit for the reductant supply system, typically in diesel engines with Selective Catalytic Reduction (SCR) systems.
How serious is the P202F code?
P202F is considered a severe code that should be addressed promptly. While it may not require immediate vehicle shutdown, prolonged driving with this issue can lead to reduced fuel efficiency, excessive emissions, and potential damage to the catalytic converter.
What are the common symptoms of P202F?
Common symptoms include reduced fuel efficiency, excessive black exhaust smoke, diminished engine performance, and illumination of the Check Engine light.
What causes the P202F code?
Common causes include a defective reductant supply pump, open or shorted circuits in the reductant supply control, faulty PCM or SCR controller, clogged DEF injector, contaminated DEF fluid, and leaks in the DEF system.
Is P202F a generic or manufacturer-specific code?
P202F is a generic powertrain code applicable to many OBD-II vehicles, particularly those with diesel engines and SCR systems.
Can I still drive my vehicle with the P202F code?
While you may be able to drive for a short time, it is recommended to have the vehicle inspected by a qualified technician as soon as possible to prevent potential damage to the SCR system or catalytic converter.
How is P202F diagnosed?
Diagnosis typically involves using an OBD-II scanner to retrieve codes and freeze frame data, inspecting DEF system components, testing the reductant supply pump with a multimeter, and checking wiring and connectors for damage.
What tools are needed to diagnose P202F?
Required tools include an OBD-II scanner, digital multimeter, and access to vehicle-specific diagnostic information.
How is P202F repaired?
Repairs may include replacing the faulty reductant supply pump, repairing or replacing damaged wiring, cleaning or replacing the DEF injector, refilling or replacing contaminated DEF fluid, or in rare cases, replacing the PCM or SCR controller.
What is the role of the reductant supply pump in relation to P202F?
The reductant supply pump pressurizes the Diesel Exhaust Fluid (DEF) for injection into the exhaust stream. A faulty pump is a common cause of P202F.
How does P202F affect vehicle emissions?
P202F can lead to increased emissions, particularly NOx, as it indicates a problem with the SCR system responsible for reducing these harmful pollutants.
Can P202F be prevented?
Regular maintenance, using high-quality DEF fluid, maintaining proper DEF levels, and promptly addressing any DEF-related warning lights can help prevent P202F.
What is the typical cost to repair P202F?
Repair costs can vary widely depending on the cause, but typically range from $300 to $800 for pump replacement, up to $1500 for more complex issues involving the PCM.
Are there any related codes that often appear with P202F?
P202F may coincide with other SCR-related codes such as P20EE (SCR NOx Catalyst Efficiency Below Threshold) and P204F (Reductant System Performance).
How long does it typically take to repair P202F?
Repair time can vary depending on the specific cause and vehicle model, but typically ranges from 1-3 hours for common repairs like pump replacement.
Can P202F cause damage to other vehicle components if left unaddressed?
Yes, prolonged operation with P202F can potentially damage the catalytic converter and other components of the exhaust aftertreatment system.
Is it safe to perform DIY repairs for P202F?
While some repairs can be performed by skilled DIYers, given the complexity of SCR systems, it is generally recommended to have P202F diagnosed and repaired by a qualified technician.
How often should the DEF system be inspected to prevent P202F?
It is recommended to visually inspect DEF system components during regular oil changes and to follow the manufacturer’s maintenance schedule for more thorough inspections.
Can using low-quality DEF fluid contribute to P202F?
Yes, using contaminated or substandard DEF fluid can potentially lead to P202F and other SCR system issues.
Will P202F affect my vehicle’s performance in ways other than emissions?
Yes, in addition to increased emissions, P202F can lead to reduced fuel efficiency and overall engine performance if left unaddressed.
Buy tested tuning file for Adblue / EGR / DPF / Adblue off now!
Register Now or Already have an account, Login now
