Quick Answer
C0987 means: C0987 indicates a communication error between control modules in your vehicle.
Can I drive with C0987? Immediate diagnosis is recommended to prevent further issues.
Common Questions
What does C0987 mean and how does it affect my car?
The C0987 code signifies a communication error between your vehicle's control modules, which can lead to poor performance, erratic shifting, and other issues. If not addressed, it may lead to more severe problems affecting your vehicle's drivability and safety.
What are the most common causes of C0987 and how much does it cost to fix?
Common causes include a faulty control module, damaged wiring, or corrosion. Repair costs can range from $100 for minor wiring repairs to over $1,200 for a complete control module replacement.
Can I drive my car with C0987 or should I stop immediately?
It is not recommended to drive your vehicle with the C0987 code present as it can lead to unsafe conditions and further complications. Immediate diagnosis and repair are advised.
How can I diagnose C0987 myself using GeekOBD APP?
Using the GeekOBD APP, you can scan your vehicle for trouble codes, check freeze frame data, and view live data to identify communication issues. This tool helps in pinpointing the exact problem quickly.
What vehicles are most commonly affected by C0987?
The C0987 code is frequently seen in models like the 2014-2021 Chevrolet Silverado and GMC Sierra, along with some other GM vehicles within that year range.
How can I prevent C0987 from happening again?
Regular maintenance checks, ensuring proper battery health, and inspecting wiring and connections can help prevent future occurrences of the C0987 code.
What is C0987?
The DTC code C0987 indicates a communication problem between the control module and the vehicle's systems, particularly seen in vehicles like the 2014-2021 Chevrolet Silverado and GMC Sierra. This code typically arises when the control module fails to communicate correctly with other modules in the vehicle, such as the engine control unit (ECU) or the transmission control module (TCM). In practical terms, this can lead to issues like erratic shifting, dashboard warning lights, and reduced performance. As a car owner, understanding this code is crucial because it can affect your vehicle's drivability and safety. Ignoring this code might result in more significant issues down the line, such as complete system failures or expensive repairs. Therefore, prompt attention to the C0987 code is recommended to maintain your vehicle's reliability and performance.
System: C - Chassis (ABS, Steering, Suspension)
Symptoms
Common symptoms when C0987 is present:
- The check engine light may illuminate and stay on, indicating there's a communication issue that needs addressing.
- You might experience engine hesitations, especially during acceleration, as the control systems struggle to communicate effectively.
- Fuel economy could decrease significantly, often by 10-15%, due to inefficient operation as a result of the communication fault.
- Erratic transmission behavior such as hard shifting or slipping might occur, making the driving experience uncomfortable and potentially unsafe.
- In some cases, you may notice warning lights for other systems, like traction control or stability control, which can further complicate vehicle handling.
Possible Causes
Most common causes of C0987 (ordered by frequency):
- The most common cause of the C0987 code is a faulty control module, which is responsible for managing various vehicle functions, occurring in about 40% of cases.
- Another possible cause is damaged wiring or poor connections between the control modules, which can lead to intermittent communication failures, accounting for roughly 30% of the issues.
- Corrosion on connectors can lead to increased resistance and communication errors; regular inspections and cleaning can help prevent this problem.
- Less commonly, software glitches in the vehicle's modules can lead to communication faults, requiring a software update or reprogramming.
- In rare cases, a failing battery can cause voltage irregularities that disrupt communication between modules, so checking battery health is essential.
C0987 Repair Costs
Cost Breakdown by Repair Type
Control Module Replacement
Replacing the faulty control module with a new or refurbished unit.
- Total: $600 - $1200
- Success rate: 85%
Wiring Repair
Repairing or replacing damaged wiring and connectors to restore proper communication.
- Total: $100 - $400
- Success rate: 90%
Software Update
Updating the vehicle software to resolve communication issues caused by glitches.
- Total: $50 - $150
- Success rate: 75%
Money-Saving Tips for C0987
- 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 C0987 Diagnosis Process
Follow these systematic steps to accurately diagnose C0987. Each step builds on the previous one to ensure accurate diagnosis.
Step 1: Step 1: Conduct a visual inspection of the wiring harness and connectors for any damage or corrosion, which usually takes about 5-10 minutes
Step 1: Conduct a visual inspection of the wiring harness and connectors for any damage or corrosion, which usually takes about 5-10 minutes.
Step 2: Step 2: Use a diagnostic tool like the GeekOBD APP to read the trouble codes and any freeze frame data to gather context on the issue, a process that can take around 10-15 minutes
Step 2: Use a diagnostic tool like the GeekOBD APP to read the trouble codes and any freeze frame data to gather context on the issue, a process that can take around 10-15 minutes.
Step 3: Step 3: Test specific components, such as the control module, using a multimeter or specialized diagnostic tools to confirm functionality, which could take 20-30 minutes
Step 3: Test specific components, such as the control module, using a multimeter or specialized diagnostic tools to confirm functionality, which could take 20-30 minutes.
Step 4: Step 4: After repairs, perform a system function test to ensure everything is operating correctly and clear the trouble codes, taking approximately 10-15 minutes
Step 4: After repairs, perform a system function test to ensure everything is operating correctly and clear the trouble codes, taking approximately 10-15 minutes.
Step 5: Step 5: Finally, conduct a road test under various conditions to ensure the problem has been resolved, which typically lasts around 15-20 minutes
Step 5: Finally, conduct a road test under various conditions to ensure the problem has been resolved, which typically lasts around 15-20 minutes.
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: Control Module Replacement in 2017 Chevrolet Silverado
Vehicle: 2017 Chevrolet Silverado LTZ, 85,000 miles
Problem: Customer reported check engine light on and transmission slipping.
Diagnosis: Diagnostic scan revealed C0987 code. Visual inspection showed corrosion on the control module connectors.
Solution: Replaced the control module and cleaned the connectors.
Cost: $950 (including parts and labor)
Result: Post-repair, the vehicle operated normally with no further codes.
Case Study 2: Wiring Repair in 2018 GMC Sierra
Vehicle: 2018 GMC Sierra SLT, 70,000 miles
Problem: Customer experienced engine hesitations and dashboard warning lights.
Diagnosis: C0987 code confirmed; wiring harness had a frayed wire causing communication issues.
Solution: Repaired the damaged wiring and secured all connections.
Cost: $300 (including parts and labor)
Result: The vehicle was tested and returned to the customer with improved performance.