AutoCodes – Chevrolet – B305C Chevrolet

B305C Chevrolet Code - Immobilizer Transponder Of Wrong Type Programmed

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: B305C Chevrolet indicates Immobilizer Transponder Of Wrong Type Programmed.
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.

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Code Popularity 468

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

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Table of contents Created and updated by William Orellana on Mar 03, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B305C Chevrolet Description

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. The transponder transmits a signal to the immobilizer control module. The immobilizer control module translates this signal to a serial data message which is sent to the Body Control Module (BCM). The BCM then compares this value to a value stored in memory. If the value is correct, the BCM will send the prerelease password via the serial data circuit to the Engine Control Module (ECM). If the learned key code does not match or a transponder value is not received, the BCM will send the start disable password to the ECM.CM.

OBDII Code B305C Chevrolet - Immobilizer Transponder Of Wrong Type Programmed - AutoCodes.com — B305C Chevrolet Code - Immobilizer Transponder Of Wrong Type Programmed

What does this mean?

What are the Possible Causes of the DTC B305C Chevrolet?

Faulty Key/Transmitter
Faulty Body Control Module (BCM)

How to Fix the DTC B305C Chevrolet?

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 B305C Chevrolet 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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About the author: William Orellana is a Master Mechanic and Mechanical Engineer with over 30 years of experience diagnosing and repairing vehicles. Learn more about his background.

Frequently Asked Questions about B305C Chevrolet Code

What does the OBDII code B305C mean on a Chevrolet?

1. The B305C code indicates that the immobilizer transponder of the wrong type has been programmed, meaning the vehicle's security system cannot properly recognize the key. 2.

What are the common symptoms of the B305C code in a Chevrolet?

Common symptoms include the engine not starting, the security light staying illuminated or flashing, and a "key not recognized" message on the dashboard. 3.

What causes the B305C code to appear in a Chevrolet?

The code is usually caused by programming the wrong type of transponder key, using a damaged or defective key, or an issue with the vehicle's immobilizer system. 4.

Can a dead key fob battery trigger the B305C code?

No, a dead key fob battery will typically prevent the fob from working but wonâ€™t trigger the B305C code since the issue relates to the transponder type, not the battery. 5.

How can the B305C code be fixed in a Chevrolet?

The code can be resolved by reprogramming the correct transponder key, replacing a defective key, or diagnosing and repairing faults in the immobilizer system. 6.

Can I clear the B305C code without fixing the issue?

Clearing the code without fixing the underlying problem will likely result in the code reappearing and the vehicle still not starting. 7.

Is the B305C code specific to certain Chevrolet models?

While it is more common in Chevrolet models with advanced immobilizer systems, it can occur in any model equipped with a transponder key security feature. 8.

How much does it cost to fix the B305C code on a Chevrolet?

Costs vary depending on the issue, but reprogramming a key typically costs $50-$150, while replacing a defective immobilizer system can cost several hundred dollars. 9.

Can I program a new key myself to fix the B305C code?

Some Chevrolet models allow DIY key programming if you have at least one working key, but others require professional tools, making it necessary to visit a dealership or locksmith. 10.

What tools are needed to diagnose the B305C code?

A professional-grade OBDII scanner with immobilizer system capabilities is needed to diagnose the B305C code and pinpoint the exact cause.