B2721 GMC Code - PASS-Key Detection Circuit
Quick Answer
The Body Control Module (BCM) supplies a 5 volt signal and a ground circuit for the PASS-Key® system. Common causes include Faulty Ignition Key, Faulty Ignition Lock Cylinder, 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
- B2721 GMC indicates PASS-Key Detection Circuit.
- Common causes
- Common causes include Faulty Ignition Key, Faulty Ignition Lock Cylinder, 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 B2721 GMC Description
What are the Possible Causes of the DTC B2721 GMC?
- Faulty Ignition Key
- Faulty Ignition Lock Cylinder
- Faulty Body Control Module (BCM)
How to Fix the DTC B2721 GMC?
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 B2721 GMC 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.
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Frequently Asked Questions about B2721 GMC Code
1. What does the OBDII code B2721 mean on a GMC?
B2721 indicates an issue with the PASS-Key detection circuit, which is part of the vehicle's theft deterrent system.
2. What are the common symptoms of a B2721 code?
Symptoms include the engine not starting, the security light staying on, or intermittent starting issues.
3. What causes the B2721 code to appear?
Common causes include a faulty ignition key or key cylinder, damaged wiring, or a malfunctioning theft deterrent module.
4. Can I still drive my GMC with a B2721 code?
It may not be possible to drive, as the code often prevents the engine from starting due to security system activation.
5. How do I diagnose the B2721 code?
Use a scan tool to confirm the code, inspect the ignition key and cylinder, and check wiring and connections for damage or corrosion.
6. What repairs are typically needed for a B2721 code?
Repairs may include replacing the ignition key, repairing damaged wiring, or replacing the theft deterrent module.
7. How much does it cost to fix a B2721 code on a GMC?
Costs vary but may range from $100 to $500, depending on the parts needing replacement and labor rates.
8. Can a dead battery trigger the B2721 code?
Yes, a low or dead battery can sometimes disrupt the theft deterrent system and cause this code to appear.
9. Can I fix the B2721 code myself?
If you have basic mechanical skills, you might replace a damaged key or inspect wiring, but more complex issues may require professional help.
10. Will clearing the code with a scanner fix the issue?
Clearing the code may temporarily reset the system, but the underlying problem must be addressed to prevent the code from returning.
Discuss the causes and fixes for B2721 GMC OBDII Code
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