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 is having trouble reading the sensor that tells it how much special fluid (called reductant or DEF) is left in the tank. It's like when your video game controller can't tell how much battery is left.
The P10AB code indicates an issue with the electrical circuit related to the second reductant level sensor, which monitors the level of Diesel Exhaust Fluid (DEF) in the vehicle.
The reductant level sensor 2 is part of the vehicle's emissions control system, specifically for diesel engines. It measures the amount of DEF in the tank, which is used to reduce harmful emissions. A malfunction in this sensor's circuit can lead to incorrect readings or failure to monitor the DEF level accurately.
• Check Engine Light is on
• Incorrect DEF level readings
• Possible limp mode activation
• Faulty reductant level sensor
• Damaged wiring or connectors
• DEF tank contamination
Reductant: A substance used to reduce emissions, commonly Diesel Exhaust Fluid (DEF) in diesel engines.
DEF: Diesel Exhaust Fluid, a liquid used in diesel engines to reduce emissions.
• Use an OBD-II scanner to confirm the code.
• Inspect the wiring and connectors for damage.
• Test the reductant level sensor for proper operation.
• Replace the reductant level sensor if faulty.
• Repair or replace damaged wiring or connectors.
• Clean or replace the DEF tank if contaminated.
• OBD-II scanner
• Multimeter
• Basic hand tools
$150 - $400
Moderate
• Ford F-250
• Chevrolet Silverado 2500
• Ram 2500
• Regularly check and refill DEF levels.
• Inspect wiring for damage during routine maintenance.
• Use high-quality DEF to avoid contamination.
Sensor Issue
• Do not ignore the Check Engine Light.
• Schedule a diagnostic check with a professional.
• Ensure DEF is topped up regularly.
Check with the vehicle manufacturer for specific warranty coverage related to emissions components.
This code has become more common with the increased use of DEF systems in diesel engines to meet emissions standards.
Moderate – Addressing this issue promptly can prevent further emissions system problems.
Ignoring emissions-related codes can lead to increased pollution and may fail emissions tests required by law.
• Engine must be running.
• DEF tank should have fluid for accurate testing.
The reductant level sensor is typically located in or near the DEF tank, which is usually mounted under the vehicle near the rear or along the side.
Q: Can I drive with a P10AB code?
A: While you can drive with this code, it's best to address it soon to avoid potential emissions issues.
Q: What happens if I ignore this code?
A: Ignoring this code can lead to incorrect DEF level readings and possible emissions test failures.
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