C0387 Buick Code - Unable to Complete Shift
Quick Answer
The C0387 diagnostic trouble code (DTC) for Buick vehicles indicates that the transmission control module (TCM) has detected an issue that is preventing the transmission from completing a shift. Common causes include Low transmission fluid level or dirty transmission fluid, Faulty transmission solenoid, Malfunctioning shift linkage. 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
- C0387 Buick indicates Unable to Complete Shift.
- Common causes
- Common causes include Low transmission fluid level or dirty transmission fluid, Faulty transmission solenoid, Malfunctioning shift linkage.
- 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.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.
Code C0387 Buick Description
The C0387 diagnostic trouble code (DTC) for Buick vehicles indicates that the transmission control module (TCM) has detected an issue that is preventing the transmission from completing a shift. This can lead to erratic shifting behavior, difficulty changing gears, or even complete transmission failure. The inability to complete a shift can significantly impact the vehicle's performance, fuel efficiency, and overall drivability.
Common Causes of C0387 Buick
- Low transmission fluid level or dirty transmission fluid
- Faulty transmission solenoid
- Malfunctioning shift linkage
- Transmission control module (TCM) failure
- Wiring or electrical issues
Symptoms of C0387 Buick
- Erratic shifting behavior
- Delayed or harsh shifting
- Stuck in a single gear
- Transmission slipping
- Illumination of the Check Engine Light
How to Fix C0387 Buick
- Begin by checking the transmission fluid level and condition. Top off or replace the fluid if necessary.
- Inspect the transmission solenoid and shift linkage for any signs of damage or wear. Replace as needed.
- Use a diagnostic scan tool to retrieve the trouble codes and reset the TCM.
- Test drive the vehicle to ensure that the shifting issue has been resolved.
- If the problem persists, further diagnosis may be required to pinpoint the exact cause of the issue.
Cost to Fix C0387 Buick
The cost of repairing a C0387 code can vary depending on the specific cause of the issue. In general, you can expect to pay anywhere from $200 to $800 for parts and labor. This estimate includes the cost of any necessary replacement parts, diagnostic time, and labor charges. Keep in mind that labor rates can vary between different auto repair shops, so it's a good idea to get quotes from multiple locations to find the best price.
Need more information about the C0387 Buick code?
Need more information on how to fix the C0387 Buick code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the C0387 Buick code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about C0387 Buick Code
1. What does the OBDII code C0387 mean on a Buick?
C0387 indicates that the vehicle's transfer case control module has detected an issue preventing the completion of a requested shift, typically in the 4WD or AWD system.
2. What are the common symptoms of code C0387 in a Buick?
Common symptoms include the inability to shift into or out of 4WD/AWD modes, warning lights on the dashboard (such as "Service 4WD"), and possible clunking or grinding noises during shift attempts.
3. What causes the C0387 code on a Buick?
The code can be caused by a faulty transfer case shift motor, damaged transfer case gears, wiring issues, or a malfunctioning transfer case control module.
4. Can a bad transfer case motor trigger the C0387 code?
Yes, a bad or stuck transfer case shift motor is one of the most common causes of the C0387 code.
5. How can I diagnose the C0387 code on my Buick?
Diagnose the issue by checking the transfer case shift motor, inspecting wiring and connectors for damage or corrosion, and using a scan tool to monitor the transfer case control module’s data.
6. Is it safe to drive with the C0387 code active?
Driving with this code may be safe in some cases, but it could compromise 4WD/AWD functionality, which may be dangerous in certain road or weather conditions.
7. How is the C0387 code typically repaired?
Repairs may include replacing the transfer case shift motor, repairing or replacing damaged wiring, or reprogramming or replacing the transfer case control module.
8. Can a software issue cause the C0387 code on a Buick?
Yes, outdated or corrupted software in the transfer case control module can sometimes cause this code, requiring a reflash or software update.
9. How much does it typically cost to fix the C0387 code on a Buick?
The cost can vary but typically ranges from $200 to $600 depending on whether the issue is with the shift motor, wiring, or control module.
10. Can lack of maintenance lead to the C0387 code?
Yes, lack of proper maintenance, such as not servicing the transfer case fluid, can lead to mechanical issues that trigger this code.
Discuss the causes and fixes for C0387 Buick OBDII Code
Code C0387 Buick comments
No comments found for this page.
Fix Your Car Smarter
Try the New AutoCodes App!
Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.