AutoCodes – Chevrolet – P248B Chevrolet

P248B Chevrolet Code - Reductant Heater 1 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: P248B Chevrolet indicates Reductant Heater 1 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 394

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 P248B Chevrolet 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 a 3 V difference between battery voltage and reductant tank heater voltage.

OBDII Code P248B Chevrolet - Reductant Heater 1 Feedback Circuit High Voltage - AutoCodes.com — P248B Chevrolet Code - Reductant Heater 1 Feedback Circuit High Voltage

What does this mean?

What are the Possible Causes of the DTC P248B Chevrolet?

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 P248B Chevrolet?

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 P248B Chevrolet 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.

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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 P248B Chevrolet Code

1. What are the common symptoms of OBDII code P248B (Chevrolet) - Reductant Heater 1 Feedback Circuit High Voltage?

- Common symptoms include the Check Engine Light coming on, reduced engine performance, and potential issues with the vehicle's emissions system.

2. What are the possible causes of OBDII code P248B (Chevrolet)?

- Possible causes include a faulty reductant heater 1, wiring issues in the feedback circuit, a malfunctioning powertrain control module (PCM), or a damaged electrical connector.

3. How serious is OBDII code P248B (Chevrolet) - Reductant Heater 1 Feedback Circuit High Voltage?

- This code should be addressed promptly as it can affect the vehicle's emissions system and potentially lead to reduced engine performance if left unresolved.

4. Can I continue driving my vehicle with OBDII code P248B (Chevrolet) present?

- It is not recommended to continue driving the vehicle with this code present, as it may lead to further damage to the emissions system and engine performance.

5. How can I diagnose OBDII code P248B (Chevrolet)?

- Diagnosis typically involves using a scan tool to retrieve the code, checking the reductant heater 1 and its wiring for faults, and testing the feedback circuit for high voltage.

6. Are there any DIY repair tips for OBDII code P248B (Chevrolet)?

- DIY repair tips include checking the electrical connections for corrosion or damage, inspecting the wiring harness for any signs of wear, and ensuring the reductant heater 1 is functioning properly.

7. How much does it cost to repair OBDII code P248B (Chevrolet) - Reductant Heater 1 Feedback Circuit High Voltage?

- Repair costs can vary depending on the exact cause of the issue, but it may involve replacing the reductant heater 1, repairing wiring, or addressing PCM issues. Costs can range from $200 to $800 or more.

8. Can a mechanic reset OBDII code P248B (Chevrolet) after repair?

- Yes, a mechanic can reset the code after the necessary repairs have been made to clear the Check Engine Light and ensure the issue has been resolved.

9. How long does it typically take to repair OBDII code P248B (Chevrolet)?

- The repair time can vary based on the exact cause of the issue and the extent of the repairs needed. In general, it may take a few hours to a full day for diagnosis and repair.

10. What should I do if OBDII code P248B (Chevrolet) keeps coming back after repair?

- If the code keeps reappearing after repair, it may indicate an underlying issue that was not fully addressed. It is recommended to have a thorough reevaluation by a qualified mechanic to determine the root cause.