Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means the car's computer has detected a problem with the sensor that checks the temperature of the special fluid tank used to clean the car's exhaust. It's like a thermometer that's not working right.
The P205C code is triggered when the vehicle's powertrain control module (PCM) detects a low voltage signal from the reductant tank temperature sensor circuit.
The reductant tank temperature sensor monitors the temperature of the diesel exhaust fluid (DEF) in the reductant tank. This sensor is crucial for ensuring the DEF is at an optimal temperature for proper emission control. A 'circuit low' condition indicates that the sensor is reporting a voltage lower than expected, which could be due to wiring issues, a faulty sensor, or problems with the PCM.
• Check Engine Light illuminated
• Poor vehicle emissions performance
• Possible reduction in engine power
• Faulty reductant tank temperature sensor
• Wiring issues or poor connections in the sensor circuit
• Defective powertrain control module (PCM)
Reductant: A substance used to reduce emissions, typically diesel exhaust fluid (DEF).
PCM: Powertrain Control Module, the vehicle's computer responsible for engine and transmission management.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage or corrosion.
• Test the reductant tank temperature sensor for proper operation.
• Repair or replace damaged wiring or connectors.
• Replace the reductant tank temperature sensor if faulty.
• Reprogram or replace the PCM if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-Series
• Chevrolet Silverado
• Ram 1500
• Regularly inspect and maintain sensor wiring.
• Ensure proper handling of DEF to avoid contamination.
• Perform routine vehicle diagnostics.
Sensor Issue
• Address the issue promptly to avoid emission problems.
• Consult a professional mechanic if unsure about repairs.
Check with the vehicle manufacturer for specific warranty coverage related to emissions components.
This code has become more common with the widespread use of DEF systems in diesel vehicles to meet emission standards.
Moderate – It should be addressed soon to ensure proper emissions control.
Ignoring this code may lead to increased emissions, which can be illegal in some regions and harmful to the environment.
• Engine at operating temperature
• Vehicle in a safe, stationary position
The reductant tank temperature sensor is typically located on or near the DEF tank, usually towards the rear of the vehicle.
Q: Can I drive with a P205C code?
A: You can drive for a short period, but it's best to fix the issue soon to avoid emissions problems.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to increased emissions and potential legal issues with vehicle inspections.
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