B3935 2017 GMC Sierra Code - Transponder Authentication
Quick Answer
When an ignition key is inserted into the ignition lock cylinder and the ignition is switched ON, the transponder embedded in the key is energized by the exciter coil surrounding the ignition lock cylinder. Common causes include Faulty Key/Transmitter, Faulty Body Control Module (BCM). 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
- B3935 2017 GMC Sierra indicates Transponder Authentication.
- Common causes
- Common causes include Faulty Key/Transmitter, Faulty Body Control Module (BCM).
- 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.
Code B3935 2017 GMC Sierra Description
What are the Possible Causes of the DTC B3935 2017 GMC Sierra?
- Faulty Key/Transmitter
- Faulty Body Control Module (BCM)
How to Fix the DTC B3935 2017 GMC Sierra?
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 B3935 2017 GMC Sierra 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.
Need more information about the B3935 2017 GMC Sierra code?
Need more information on how to fix the B3935 2017 GMC Sierra code? Get Access to Factory Service Manuals
Need Help with the Code?
Get the B3935 2017 GMC Sierra code diagnosed by a professional: Find a repair shop in your area
Frequently Asked Questions about B3935 2017 GMC Sierra Code
1. What does the OBDII code B3935 mean on a 2017 GMC Sierra?
The code B3935 indicates an issue with the Transponder Authentication system, which is responsible for verifying the key's security code during engine start.
2. What are the common symptoms of the B3935 code on a GMC Sierra?
Symptoms may include the engine not starting, security light illumination on the dashboard, or intermittent starting issues.
3. What causes the B3935 code to appear?
Common causes include a malfunctioning transponder key, a damaged ignition switch, wiring issues, or a fault in the vehicle's theft deterrent module.
4. Can I still drive my GMC Sierra with the B3935 code?
If the engine starts, you can drive the vehicle, but the issue may worsen over time. It's best to address it promptly to avoid being locked out of starting your vehicle.
5. How can I fix the B3935 code on my 2017 GMC Sierra?
Repairs might involve reprogramming or replacing the transponder key, inspecting and repairing wiring connections, or replacing the theft deterrent module.
6. How do I know if my transponder key is faulty for the B3935 code?
If you use a spare key and the issue resolves, the original transponder key may be faulty and require replacement or reprogramming.
7. Can a dead key fob battery cause the B3935 code?
No, a dead key fob battery typically won't trigger the B3935 code because it relates to the transponder chip, not the remote functions.
8. How much does it cost to fix the B3935 code on a GMC Sierra?
The cost depends on the exact issue, but replacing or reprogramming a key may cost $50-$300, while module repairs could range from $200-$800.
9. Do I need a professional to fix the B3935 code?
Yes, diagnosing and fixing this code often requires specialized equipment to reprogram keys or diagnose the theft deterrent system.
10. Can disconnecting the battery clear the B3935 code?
No, disconnecting the battery won't solve the underlying issue. The code will likely return unless the root cause is addressed.
Discuss the causes and fixes for B3935 2017 GMC Sierra OBDII Code
Code B3935 2017 GMC Sierra 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.
