P20B9 2018 Chevrolet Silverado Code - Reductant Heater 1 Control Circuit
Quick Answer
As reductant will freeze at temperatures below -11°C (12°F), there are 2 reductant heaters located in the reductant tank. Common causes include Faulty Reductant Heater, Reductant Heater harness is open or shorted, Reductant Heater circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
- What it means
- P20B9 2018 Chevrolet Silverado indicates Reductant Heater 1 Control Circuit.
- Common causes
- Common causes include Faulty Reductant Heater, Reductant Heater harness is open or shorted, Reductant Heater circuit poor electrical connection.
- Severity
- High - diagnose this code as soon as possible.
- Can I drive?
- Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.
Code P20B9 2018 Chevrolet Silverado Description
The Diagnostic Trouble Code (DTC) will be set when the ECM indicates the reductant tank heater control circuit is open for greater than 4 s.
What are the Possible Causes of the DTC P20B9 2018 Chevrolet Silverado?
- Faulty Reductant Heater
- Reductant Heater harness is open or shorted
- Reductant Heater circuit poor electrical connection
- Faulty Reductant Pump and Sensor Assembly
- Faulty Reductant Control Module
How to Fix the DTC P20B9 2018 Chevrolet Silverado?
Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.
What is the Cost to Diagnose the Code?
Labor: 1.0
To diagnose the P20B9 2018 Chevrolet Silverado code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.
Need more information about the P20B9 2018 Chevrolet Silverado code?
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Frequently Asked Questions about P20B9 2018 Chevrolet Silverado Code
1. What does the OBDII code P20B9 mean on a 2018 Chevrolet Silverado?
P20B9 indicates an issue with the Reductant Heater 1 Control Circuit, which is responsible for heating the diesel exhaust fluid (DEF) to ensure proper operation in cold temperatures.
2. What are common symptoms of code P20B9 in a 2018 Chevrolet Silverado?
Symptoms may include the check engine light turning on, reduced engine performance, DEF system warnings, and difficulty starting the vehicle in cold weather.
3. What causes the P20B9 code to appear on a 2018 Chevrolet Silverado?
Common causes include a faulty reductant heater, damaged wiring or connectors in the heater circuit, a blown fuse, or a malfunctioning powertrain control module (PCM).
4. Can I drive my 2018 Chevrolet Silverado with the P20B9 code active?
While the vehicle may still be drivable, prolonged operation with this code can lead to reduced engine performance and potential DEF system failure in cold weather.
5. How do I diagnose the P20B9 code on my 2018 Chevrolet Silverado?
Diagnosis involves checking the DEF heater wiring and connectors for damage, testing the heater's electrical resistance, and verifying power and ground signals with a multimeter.
6. How can I fix the P20B9 code on a 2018 Chevrolet Silverado?
Repairs may include replacing the reductant heater, repairing damaged wiring or connectors, replacing a blown fuse, or reprogramming or replacing the PCM if necessary.
7. How much does it cost to repair the P20B9 code on a 2018 Chevrolet Silverado?
The cost can vary, but replacing the reductant heater typically ranges from $300 to $800, depending on labor rates and parts pricing.
8. What tools are needed to address the P20B9 code on a 2018 Chevrolet Silverado?
Basic tools include a diagnostic scanner, multimeter, and possibly a repair manual for the truck. Advanced repairs may require specialized tools for DEF system components.
9. Does the P20B9 code affect emissions compliance on a 2018 Chevrolet Silverado?
Yes, a malfunctioning DEF system can lead to increased emissions, and the vehicle may fail an emissions test if this issue is not resolved.
10. Is the P20B9 code covered under warranty for a 2018 Chevrolet Silverado?
In some cases, issues with the DEF system may be covered under the emissions warranty. Check with your dealership or warranty policy for details.
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