AutoCodes – Generic – P248D

P248D Code - Reductant Heater 2 Feedback Circuit High Voltage

Quick Answer

As reductant will freeze at temperatures below -11°C (12°F), there are 2 reductant heaters located in the reductant tank. Common causes include Faulty Reductant Line Heater, Reductant Line Heater harness is open or shorted, Reductant Line Heater circuit poor electrical connection. Severity is High - diagnose this code as soon as possible. Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

What it means: P248D indicates Reductant Heater 2 Feedback Circuit High Voltage.
Common causes: Common causes include Faulty Reductant Line Heater, Reductant Line Heater harness is open or shorted, Reductant Line Heater circuit poor electrical connection.
Severity: High - diagnose this code as soon as possible.
Can I drive?: Driving is not recommended if the warning light is flashing, the engine runs poorly, or safety-related symptoms are present.

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Code Popularity 842

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jul 29, 2021

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P248D Description

As reductant will freeze at temperatures below -11°C (12°F), there are 2 reductant heaters located in the reductant tank. One heats the reductant in the tank, and one heats the reductant supplied to the reductant injector supply pipe. The Engine Control Module (ECM) monitors the reductant temperature in the tank in order to determine if the reductant temperature is below its freeze point. If the ECM determines that the reductant may be frozen, it activates a defrost strategy energizing the reductant heater. This energizing action terminates when the temperature sensor measures a threshold value over which the heater must be deactivated. The Diagnostic Trouble Code (DTC) will be set when there is greater than 3 V difference between battery voltage and reductant line heater voltage.

OBDII Code P248D - Reductant Heater 2 Feedback Circuit High Voltage - AutoCodes.com — P248D Code - Reductant Heater 2 Feedback Circuit High Voltage

What does this mean?

What are the Possible Causes of the DTC P248D?

Faulty Reductant Line Heater
Reductant Line Heater harness is open or shorted
Reductant Line Heater circuit poor electrical connection
Faulty Reductant Pump and Sensor Assembly
Faulty Reductant Control Module

How to Fix the DTC P248D?

Review the 'Possible Causes' above and visually examine the corresponding wiring harness and connectors. Check for damaged components and inspect connector pins for signs of being broken, bent, pushed out, or corroded.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P248D code, it typically requires 1.0 hour of labor. Rates vary by location, vehicle, and shop. Many shops charge between $80–$150 per hour; dealerships and metro areas may be higher, independents may be lower.

Need more information about the P248D code?

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Need Help with the Code?

Get the P248D code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P248D Buick — Reductant Heater 2 Feedback Circuit High Voltage
P248D Cadillac — Reductant Heater 2 Feedback Circuit High Voltage
P248D Chevrolet — Reductant Heater 2 Feedback Circuit High Voltage
P248D GMC — Reductant Heater 2 Feedback Circuit High Voltage

About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about P248D Code

1. What are the common symptoms of OBDII code P248D (Reductant Heater 2 Feedback Circuit High Voltage)?

The common symptoms of code P248D include the check engine light illuminating on the dashboard, reduced engine performance, and potential issues with the vehicle's emissions system.

2. What are the possible causes of OBDII code P248D?

Possible causes of code P248D can include a faulty reductant heater 2, damaged wiring or connectors in the heater circuit, a defective powertrain control module (PCM), or a software issue within the PCM.

3. How can I diagnose OBDII code P248D?

Diagnosing code P248D involves using an OBDII scanner to read the code and identify the specific issue. Further diagnostic steps may include testing the reductant heater 2, inspecting related wiring and connectors, and checking for any other potential faults in the system.

4. Can I continue driving with OBDII code P248D present?

It is not recommended to continue driving with code P248D present, as it can lead to further damage to the vehicle's emissions system and potentially affect engine performance. It is best to address the issue promptly to avoid more serious problems.

5. How can I repair OBDII code P248D?

Repairing code P248D may involve replacing the reductant heater 2, repairing or replacing damaged wiring or connectors, resetting the PCM, or updating the software in the PCM. It is advisable to consult a professional mechanic for the most accurate diagnosis and repair.

6. Is OBDII code P248D related to emissions compliance?

Yes, code P248D is related to the vehicle's emissions system, specifically the reductant heater circuit. Addressing this code is important for maintaining emissions compliance and ensuring the vehicle runs efficiently.

7. Can weather conditions affect OBDII code P248D?

Extreme weather conditions, such as very low temperatures, can potentially impact the operation of the reductant heater and trigger code P248D. It's important to consider environmental factors when diagnosing and repairing this code.

8. How long does it typically take to repair OBDII code P248D?

The repair time for code P248D can vary depending on the specific cause of the issue and the complexity of the repair. In some cases, it may be a relatively quick fix, while in others, it may require more extensive troubleshooting and part replacement.

9. Can I reset the check engine light after repairing OBDII code P248D?

Once the underlying issue causing code P248D has been repaired, the check engine light can be reset using an OBDII scanner. This will clear the code from the vehicle's system and turn off the warning light on the dashboard.

10. Are there any preventive maintenance tips to avoid OBDII code P248D in the future?

To help prevent code P248D from occurring in the future, it is recommended to follow the manufacturer's recommended maintenance schedule, including regular inspections of the emissions system components and addressing any issues promptly to avoid more serious problems.