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 the car that keeps a special fluid warm. This fluid helps clean the car's exhaust, but if it gets too cold, it won't work right.
The P202A code indicates that the engine control module (ECM) has detected an issue with the circuit that controls the heater for the reductant tank. This heater is necessary to keep the diesel exhaust fluid (DEF) from freezing in cold temperatures.
The reductant tank heater is responsible for maintaining the diesel exhaust fluid at a temperature where it remains in a liquid state, even in cold weather. The P202A code is triggered when the ECM detects an open circuit or a malfunction in the heater control circuit, which can prevent the DEF from being properly heated.
• Check Engine Light illuminated
• Reduced engine performance
• Possible increase in emissions
• Faulty reductant tank heater
• Damaged wiring or connectors in the heater circuit
• Blown fuse related to the heater circuit
Reductant: A substance that reduces emissions in diesel engines, often referring to diesel exhaust fluid.
DEF: Diesel Exhaust Fluid, a liquid used to reduce emissions in diesel engines.
• Use an OBD-II scanner to confirm the P202A code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the reductant tank heater for continuity and proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the reductant tank heater if faulty.
• Replace any blown fuses related to the heater circuit.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regularly inspect wiring and connectors for damage.
• Ensure the DEF tank is adequately filled.
• Perform regular maintenance checks on the DEF system.
Sensor Issue
• Do not ignore the check engine light; have the vehicle inspected.
• Avoid driving in extremely cold conditions until repaired.
• Consult with a professional mechanic for accurate diagnosis.
Check with the vehicle manufacturer for specific warranty coverage on emission-related components.
The P202A code has become more common with the increased use of diesel engines equipped with DEF systems to meet emissions standards.
Moderate – Addressing this issue is important to maintain vehicle performance and emissions compliance.
Ignoring this code may lead to increased emissions, which can be illegal in some regions. It may also affect vehicle performance and fuel efficiency.
• Cold weather conditions
• Vehicle at operating temperature
The reductant tank heater is typically located near or inside the diesel exhaust fluid tank, usually at the rear of the vehicle.
Q: Can I drive with a P202A code?
A: While you may be able to drive, it's not recommended as it can lead to increased emissions and reduced engine performance.
Q: What is diesel exhaust fluid?
A: Diesel exhaust fluid (DEF) is a solution used in diesel engines to reduce harmful emissions. It helps convert nitrogen oxides into harmless nitrogen and water.
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