U0C90 - Understanding the Diagnostic Trouble Code for 2015-2018 Honda Accord and Other Models

Quick Answer

U0C90 means: DTC U0C90 indicates a communication error within the vehicle's control modules, primarily involving the Body Control Module.

Fix: Check and replace faulty components Cost: $100 - $300 Time: 90-180 minutes

Can I drive with U0C90? It is recommended to address this issue immediately to avoid further complications.

Common Questions

What does U0C90 mean and how does it affect my car?

The U0C90 code signifies a communication error within the control modules of your vehicle. This can lead to various electrical problems, such as malfunctioning lights and issues with ignition or vehicle starting. If left untreated, it can cause more serious electrical failures, affecting overall vehicle performance and safety.

What are the most common causes of U0C90 and how much does it cost to fix?

Common causes include wiring problems, faulty BCMs, and corroded connectors. Repair costs can range from $100 for minor wiring fixes to $700 for BCM replacements, depending on the severity and complexity of the issue.

Can I drive my car with U0C90 or should I stop immediately?

While it may be possible to drive your vehicle short distances, it is not recommended to ignore the U0C90 code. Doing so could lead to further electrical complications, potential safety risks, and more costly repairs.

How can I diagnose U0C90 myself using GeekOBD APP?

To diagnose U0C90 using the GeekOBD APP, connect your device to the vehicle's OBD2 port, run a full scan, and note the codes and freeze frame data. Pay attention to any additional codes that may provide context for U0C90, and follow up with visual inspections of wiring and connectors.

What vehicles are most commonly affected by U0C90?

DTC U0C90 is often seen in models like the 2015-2018 Honda Accord, as well as other vehicles with similar electronic configurations. Manufacturers may have specific Technical Service Bulletins (TSBs) addressing this code.

How can I prevent U0C90 from happening again?

Regular maintenance, including inspections of wiring and connectors, can help prevent U0C90. Additionally, avoid aftermarket modifications that may interfere with the vehicle's electrical systems, and ensure software updates are performed as recommended by the manufacturer.

What is U0C90?

The DTC U0C90 is a communication error code that indicates a malfunction related to the vehicle's communication network, particularly affecting the Body Control Module (BCM) and other control modules. This code can often arise in vehicles like the 2015-2018 Honda Accord, as well as some other models from various manufacturers. When this code appears, it typically signifies that there is a disruption in the data transmission between the control modules, which can lead to a variety of issues including malfunctioning lights, door locks, or even the inability to start the vehicle. It is essential for drivers to address this code promptly because unaddressed communication problems can escalate, leading to more significant electrical issues. In many cases, the presence of DTC U0C90 may also trigger other related codes, complicating the diagnostic process. Therefore, understanding the implications of this code is crucial for maintaining optimal vehicle performance and safety.

System: U - Network (Communication, CAN Bus)

Symptoms

Common symptoms when U0C90 is present:

  • Check engine light remains illuminated, indicating a persistent issue with the vehicle's systems.
  • Malfunctioning interior lights or dashboard displays, where lights may flicker or fail to operate correctly.
  • Problems with power windows or door locks, leading to inoperability or intermittent operation.
  • Engine may hesitate or fail to start due to communication issues affecting the ignition system.
  • Erratic behavior of electronic accessories, such as radio or climate control settings resetting unexpectedly.

Possible Causes

Most common causes of U0C90 (ordered by frequency):

  1. Wiring issues: The most common cause (approximately 40%) involves damaged wiring or loose connections within the vehicle's communication harness, which can disrupt signals between modules.
  2. Faulty Body Control Module (BCM): A malfunctioning BCM, which is responsible for various electronic functions, can lead to a communication failure; this is usually the second most common cause.
  3. Corroded connectors: Corrosion at connection points can impede signal transmission, contributing to the U0C90 code; regular maintenance can help prevent this.
  4. Aftermarket modifications: Installation of aftermarket accessories without proper integration can create conflicts within the vehicle's electrical system.
  5. Software glitches: Rarely, software issues in the control modules can lead to erroneous communication errors, requiring updates or reprogramming.

U0C90 Repair Costs

Cost Breakdown by Repair Type

Wiring Repair

Repair of damaged wiring and reconnection of loose connectors.

  • Total: $100 - $300
  • Success rate: 85%
Body Control Module Replacement

Replacement of a faulty BCM if repairs are not feasible.

  • Total: $400 - $700
  • Success rate: 90%
Money-Saving Tips for U0C90
  • 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 U0C90 Diagnosis Process

Follow these systematic steps to accurately diagnose U0C90. 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 or specific diagnostic tools to test suspected components, focusing on the BCM and related wiring (20-30 minutes)

Step 3: Component testing - Use a multimeter or specific diagnostic tools to test suspected components, focusing on the BCM and related wiring (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 of all electrical functions after repairs and clear codes (10-15 minutes)

Step 4: System function test - Verify proper operation of all electrical functions after repairs and clear codes (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 and monitor for recurrence of the code (15-20 minutes)

Step 5: Road test verification - Drive the vehicle under various conditions to confirm repair success and monitor for recurrence of the code (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: Repair of U0C90 in 2016 Honda Accord

Vehicle: 2016 Honda Accord, 80,000 miles

Problem: Customer reported dashboard lights flickering and intermittent power window failures.

Diagnosis: After scanning with GeekOBD, U0C90 was identified along with a few additional codes related to the BCM. A visual inspection revealed corroded connectors.

Solution: Replaced corroded connectors and repaired the wiring harness. Cleared the codes and performed a function test.

Cost: $250 for parts and labor.

Result: All functions restored, no reoccurrence of U0C90 after a follow-up road test.

Case Study 2: BCM Replacement for U0C90 in 2017 Honda Civic

Vehicle: 2017 Honda Civic, 50,000 miles

Problem: Customer experienced starting issues and random electrical failures.

Diagnosis: GeekOBD scan revealed U0C90 and other communication-related codes. Inspection showed no visible wiring issues, leading to a BCM diagnostic test.

Solution: Replaced the faulty BCM and reprogrammed the vehicle's computer systems.

Cost: $650 total, including parts and labor.

Result: Vehicle started reliably, and all electrical functions resumed normal operation.

Diagnose U0C90

Use GeekOBD APP for professional diagnosis!

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  • Step-by-step repair guidance
  • Professional-grade analysis
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Code Information

Code: U0C90
System: Network (Communication, CAN Bus)
Severity: HIGH
Category: Network Codes