Easy one-page printout for the garage or repair shop
This summary uses the existing diagnostic information shown in full below.
This code means that the car's computer thinks the temperature reading from a part that helps start the car when it's cold doesn't make sense. It's like if your thermometer said it was 100 degrees in the snow!
The vehicle's control module has detected an implausible temperature reading from the DC/DC converter during a cold start.
The P1C1C code indicates that the temperature sensor in the DC/DC converter circuit is providing a reading that is outside the expected range during a cold start condition. The DC/DC converter is responsible for converting high voltage to low voltage to power the vehicle's electrical systems. An implausible temperature reading suggests a possible sensor malfunction or an issue with the converter's operation.
• Check Engine Light is on
• Difficulty starting the vehicle in cold conditions
• Reduced electrical system performance
• Faulty temperature sensor
• Wiring issues in the sensor circuit
• Malfunctioning DC/DC converter
DC/DC Converter: A device that converts high voltage to low voltage in electric and hybrid vehicles.
Temperature Sensor: A sensor that measures the temperature of a component or system.
• Use an OBD-II scanner to confirm the P1C1C code.
• Inspect the wiring and connections to the temperature sensor.
• Test the temperature sensor for proper operation.
• Replace the faulty temperature sensor.
• Repair or replace damaged wiring or connectors.
• Replace the DC/DC converter if necessary.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $500
Moderate
• Toyota Prius
• Chevrolet Volt
• Nissan Leaf
• Regular maintenance checks
• Ensure proper electrical connections
• Avoid extreme temperature exposure
Sensor Issue
• Have the vehicle inspected by a professional if the Check Engine Light is on.
• Avoid driving in extremely cold conditions until the issue is resolved.
Check with the vehicle manufacturer for warranty coverage on emissions-related components.
This code is often seen in hybrid and electric vehicles due to their reliance on DC/DC converters.
Moderate – It's important to address this issue to ensure reliable vehicle operation, especially in cold weather.
Driving with an unresolved issue may lead to further vehicle damage or reduced performance.
• Cold start condition
• Vehicle at rest
The DC/DC converter is typically located in the engine bay near the battery or under the vehicle.
Q: Can I drive with a P1C1C code?
A: It's best to have the issue checked as soon as possible, especially if you experience starting issues.
Q: What happens if I ignore this code?
A: Ignoring the code can lead to starting problems and reduced performance of the vehicle's electrical systems.
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