B0249 - Understanding the Air Conditioning System Malfunction in 2015-2018 Honda Accord

Quick Answer

B0249 means: B0249 indicates a malfunction within the air conditioning system related to the compressor relay or circuit.

Fix: Check and replace faulty components Cost: $50 - $150 Time: 90-180 minutes

Can I drive with B0249? Address this issue promptly to avoid further damage to the A/C system.

Common Questions

What does B0249 mean and how does it affect my car?

The B0249 code indicates a problem with your vehicle's air conditioning system, specifically relating to the compressor relay or circuit. If ignored, it can lead to reduced comfort in your vehicle and may cause further damage to the A/C components, leading to costly repairs.

What are the most common causes of B0249 and how much does it cost to fix?

Common causes include a faulty A/C compressor relay, damaged wiring, or a malfunctioning A/C control module. Repair costs can range from $50 for relay replacement to $600 for control module replacement, depending on the specific issue.

Can I drive my car with B0249 or should I stop immediately?

While it's possible to drive with a B0249 code, it's advisable to address the issue promptly. Driving without a functioning A/C can lead to discomfort and may cause additional strain on your vehicle's engine.

How can I diagnose B0249 myself using GeekOBD APP?

You can use the GeekOBD APP to scan for DTCs, view live data from the A/C system, and monitor the performance of related components. Look for any anomalies in the readings, which can help you pinpoint the issue.

What vehicles are most commonly affected by B0249?

The B0249 code is frequently seen in vehicles like the 2015-2018 Honda Accord, Toyota Camry, and Nissan Altima. It's important to check for any recalls or Technical Service Bulletins (TSBs) related to the A/C system for your specific make and model.

How can I prevent B0249 from happening again?

Regular maintenance checks of your A/C system, including inspecting wiring and relays, can help prevent future issues. Ensure the refrigerant levels are adequate and that any leaks are promptly repaired.

What is B0249?

The diagnostic trouble code (DTC) B0249 indicates a malfunction within the air conditioning (A/C) system, particularly relating to the compressor relay circuit or the A/C module. This code is often seen in vehicles like the 2015-2018 Honda Accord but can also affect other makes and models like the Toyota Camry and Nissan Altima. When this code is triggered, it typically means that the A/C system is not functioning as intended, which can manifest in various symptoms such as poor cooling performance or complete A/C failure. The root cause can range from a simple blown fuse to more complex issues like wiring faults, relay failures, or even problems within the A/C control module itself. Ignoring this code can lead to further damage to the A/C system components and potentially higher repair costs down the line. Therefore, early detection and resolution are crucial for maintaining your vehicle's comfort and operational efficiency.

System: B - Body (Airbags, Lighting, Security, Climate Control)

Symptoms

Common symptoms when B0249 is present:

  • The check engine light may illuminate, indicating that the vehicle's A/C system is not functioning correctly.
  • Drivers may notice that the A/C blows warm air instead of cold, which can be especially uncomfortable in hot weather.
  • A decrease in fuel economy can occur as the engine works harder to compensate for the malfunctioning A/C system, potentially leading to a 5-10% drop in efficiency.
  • Unusual noises may be heard from the A/C compressor when it is engaged, indicating that it may be struggling to operate properly.
  • In some cases, drivers may experience intermittent cooling, where the A/C works sporadically, leading to frustration.

Possible Causes

Most common causes of B0249 (ordered by frequency):

  1. The most common cause of the B0249 code is a faulty A/C compressor relay, which has a likelihood of about 40%. The relay controls the power to the compressor, and if it fails, the A/C system may not operate.
  2. Another frequent issue is damaged wiring or connections within the A/C system, accounting for around 30% of cases. Corrosion or wear can lead to poor connectivity, resulting in system malfunctions.
  3. A less common root cause includes a malfunctioning A/C control module, which can represent about 20% of cases. This module is responsible for controlling the A/C operation, and if it fails, it can lead to a complete loss of function.
  4. Rarely, refrigerant leaks can also cause this code to appear, particularly if the system is low on refrigerant. This can lead to system pressure issues that trigger the B0249 code.
  5. In some instances, a blown fuse related to the A/C system can trigger this code, though it is much less common and typically easy to rectify.

B0249 Repair Costs

Cost Breakdown by Repair Type

A/C Compressor Relay Replacement

Replacing the faulty A/C compressor relay to restore function to the A/C system.

  • Total: $50 - $150
  • Success rate: 95%
Wiring Repair

Repairing or replacing damaged wiring and connectors related to the A/C system.

  • Total: $100 - $300
  • Success rate: 90%
A/C Control Module Replacement

Replacing a malfunctioning A/C control module if other repairs do not resolve the issue.

  • Total: $300 - $600
  • Success rate: 85%
Money-Saving Tips for B0249
  • Start with the most common and least expensive repairs first
  • Use GeekOBD APP to confirm diagnosis before replacing expensive parts
  • Consider preventive maintenance to avoid future occurrences
  • Compare prices for OEM vs aftermarket parts based on your needs
  • Address the issue promptly to prevent more expensive secondary damage

Diagnostic Steps

Professional B0249 Diagnosis Process

Follow these systematic steps to accurately diagnose B0249. Each step builds on the previous one to ensure accurate diagnosis.

Step 1: Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion (5-10 minutes)

Step 1: Initial visual inspection - Check for obvious signs like damaged wiring, loose connections, or corrosion (5-10 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 2: Step 2: OBD2 scan with GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context (10-15 minutes)

Step 2: OBD2 scan with GeekOBD APP - Retrieve all codes and freeze frame data to understand the fault context (10-15 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 3: Step 3: Component testing - Use a multimeter to test the A/C compressor relay and inspect wiring continuity (20-30 minutes)

Step 3: Component testing - Use a multimeter to test the A/C compressor relay and inspect wiring continuity (20-30 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 4: Step 4: System function test - Verify proper operation after repairs and clear codes using the GeekOBD APP (10-15 minutes)

Step 4: System function test - Verify proper operation after repairs and clear codes using the GeekOBD APP (10-15 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.
Step 5: Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success, ensuring the A/C functions correctly (15-20 minutes)

Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success, ensuring the A/C functions correctly (15-20 minutes).

GeekOBD APP Tip: Use GeekOBD APP to monitor real-time data during this diagnostic step for accurate results and professional-grade analysis.

Important Notes

  • Always verify the repair with GeekOBD APP after completing diagnostic steps
  • Clear codes and test drive to ensure the problem is resolved
  • Address underlying causes to prevent code recurrence

Real Repair Case Studies

Case Study 1: A/C Repair for 2016 Honda Accord

Vehicle: 2016 Honda Accord, 45,000 miles

Problem: Customer complained of warm air blowing from A/C and check engine light on.

Diagnosis: Diagnostic scan revealed B0249 code. Visual inspection highlighted a burnt A/C compressor relay.

Solution: Replaced the A/C compressor relay, cleared the code, and recharged the A/C system.

Cost: $120 (relay: $30, labor: $90)

Result: Customer reported immediate improvement, with A/C blowing cold air and no further issues.

Case Study 2: Wiring Issues in 2017 Toyota Camry

Vehicle: 2017 Toyota Camry, 30,000 miles

Problem: A/C intermittently failed, with check engine light occasionally illuminating.

Diagnosis: B0249 code confirmed. Wiring inspection revealed corroded connectors affecting the A/C relay.

Solution: Repaired the wiring and replaced corroded connectors.

Cost: $250 (wiring repair: $150, labor: $100)

Result: A/C functioned properly post-repair, with no further fault codes.

Diagnose B0249

Use GeekOBD APP for professional diagnosis!

  • Real-time data monitoring
  • Advanced diagnostic features
  • Step-by-step repair guidance
  • Professional-grade analysis
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Code Information

Code: B0249
System: Body (Airbags, Lighting, Security, Climate Control)
Severity: MEDIUM
Category: Body Codes