Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means there's a problem with the part of your car that heats up a special fluid used to clean the exhaust. It's like when a heater in your house isn't working right.
The P20C0 code indicates that the control circuit for the second reductant heater is experiencing a high voltage condition.
The reductant heater is part of the Selective Catalytic Reduction (SCR) system, which reduces emissions by injecting a urea-based fluid into the exhaust. Heater B is responsible for ensuring the fluid remains at an optimal temperature. A 'high' circuit condition suggests excessive voltage is detected, which may be due to a short circuit or a malfunctioning control module.
• Check Engine Light is on
• Possible reduction in fuel efficiency
• Increased emissions
• Faulty reductant heater
• Wiring issues such as a short to voltage
• Defective control module
SCR: Selective Catalytic Reduction, a system to reduce emissions.
Reductant: A fluid, often urea-based, used in SCR systems to reduce emissions.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the reductant heater for proper operation.
• Replace the reductant heater if faulty.
• Repair or replace damaged wiring or connectors.
• Replace the control module if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regular maintenance of the SCR system
• Inspect wiring for damage periodically
• Use high-quality reductant fluid
Sensor Issue
• Do not ignore the Check Engine Light.
• Consult a professional mechanic if unsure.
• Avoid driving long distances until repaired.
Check with the manufacturer; emissions-related components may have extended warranties.
This code has become more common with the introduction of stricter emissions regulations and the increased use of SCR systems.
Moderate – Addressing this issue promptly can prevent further emissions-related problems.
Driving with this issue may result in failing emissions tests and could lead to fines or penalties.
• Engine running
• Ambient temperature within normal range
The reductant heater is typically located near the SCR system or along the exhaust system.
Q: Can I drive with a P20C0 code?
A: It's not recommended to drive for extended periods, as it may increase emissions and decrease fuel efficiency.
Q: How do I reset the Check Engine Light after repair?
A: Use an OBD-II scanner to clear the code after repairs are completed.
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