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 there's a problem with the sensors that check how much special fluid is left in the car. The sensors are not agreeing with each other.
The car's computer compares readings from two sensors that measure the level of reductant (a fluid used in diesel engines to reduce pollution). If the readings don't match, it triggers this code.
The P2D5A code is set when the Engine Control Module (ECM) detects a discrepancy between the readings of the reductant level sensors A and B. These sensors are responsible for monitoring the amount of Diesel Exhaust Fluid (DEF) in the tank. A correlation error indicates that the sensors are providing inconsistent data, which could affect the emission control system.
• Check engine light illuminated
• Possible reduction in engine performance
• Increased emissions
• DEF warning light on
• Faulty reductant level sensor A
• Faulty reductant level sensor B
• Wiring issues or poor connections
• DEF tank contamination or blockage
• ECM software issues
Reductant: A fluid used in diesel engines to reduce emissions.
DEF: Diesel Exhaust Fluid, a solution used to reduce nitrogen oxide emissions.
• Use an OBD-II scanner to confirm the code
• Inspect the wiring and connectors for sensors A and B
• Check the DEF tank for contamination or blockages
• Test the sensors for proper operation
• Update ECM software if necessary
• Replace faulty reductant level sensor
• Repair or replace damaged wiring/connectors
• Clean DEF tank and refill with fresh fluid
• Reprogram or update ECM software
• OBD-II scanner
• Multimeter
• Wrench set
• Diagnostic software for ECM
$150 - $500
Moderate
• Ford F-250
• Chevrolet Silverado
• Ram 2500
• Regularly check and maintain DEF levels
• Inspect and clean DEF tank periodically
• Ensure sensors and wiring are in good condition
Sensor Issue
• Avoid driving with low DEF levels
• Have the vehicle inspected if the check engine light illuminates
• Follow the manufacturer's maintenance schedule
Check with the manufacturer for warranty coverage on emission-related components.
This code has become more common with the increased use of DEF systems in diesel engines to meet emission standards.
Moderate – It should be addressed soon to prevent potential emission issues.
Ignoring this code may lead to increased emissions, which could violate environmental regulations.
• Engine at operating temperature
• DEF tank at least 50% full
The reductant level sensors are located in or near the Diesel Exhaust Fluid tank, usually at the rear of the vehicle.
Q: Can I drive with a P2D5A code?
A: It's possible to drive, but it's recommended to fix the issue soon to avoid emission problems.
Q: What happens if I ignore the P2D5A code?
A: Ignoring the code can lead to increased emissions and potential fines if the vehicle fails an emissions test.
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