AutoCodes – Generic – B3033

B3033 Code - Security System Indicates Tamper

Quick Answer

The Passlock™ system is provided in order to prevent vehicle theft if the ignition lock cylinder is forced to rotate or the ignition switch is operated while separated from the ignition lock cylinder case. Common causes include Faulty Passlockâ„¢ Sensor, Passlockâ„¢ Sensor harness is open or shorted, Passlockâ„¢ Sensor circuit poor electrical connection. 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: B3033 indicates Security System Indicates Tamper.
Common causes: Common causes include Faulty Passlockâ„¢ Sensor, Passlockâ„¢ Sensor harness is open or shorted, Passlockâ„¢ Sensor circuit poor electrical connection.
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 978

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Advanced (Pro) (3 / 3)

What is this?

Table of contents Created and updated by William Orellana on Mar 01, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B3033 Description

The Passlock™ system is provided in order to prevent vehicle theft if the ignition lock cylinder is forced to rotate or the ignition switch is operated while separated from the ignition lock cylinder case. The Body Control Module (BCM) provides security system sensor power and low reference for the Passlock™ Sensor. The BCM also measures the security system sensor voltage.
When the correct key is used to start the vehicle, a magnet on the lock cylinder passes close to the Passlock™ sensor within the ignition lock cylinder case. The magnet activates the security hall effect sensor in the Passlock™ sensor which completes a circuit from the security sensor signal circuit through a resistor to the security sensor low reference circuit. The resistance value will vary from vehicle to vehicle. The BCM will measure the voltage on the security sensor signal circuit and compare this voltage to a previously learned voltage. If the voltage measured is within the valid range, the BCM will send a class 2 message to the Powertrain Control Module (PCM) to enable vehicle starting. If the voltage measured is not within the valid range, a class 2 message will be sent to the PCM to disable starting of the vehicle.

OBDII Code B3033 - Security System Indicates Tamper - AutoCodes.com — B3033 Code - Security System Indicates Tamper

What does this mean?

What are the Possible Causes of the DTC B3033?

Faulty Passlockâ„¢ Sensor
Passlockâ„¢ Sensor harness is open or shorted
Passlockâ„¢ Sensor circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B3033?

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 B3033 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 B3033 code?

Need more information on how to fix the B3033 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B3033 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

B3033 Buick — Security System Indicates Tamper
B3033 Cadillac — Security System Indicates Tamper
B3033 Chevrolet — Security System Indicates Tamper
B3033 GMC — Security System Indicates Tamper

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 B3033 Code

1. What does the OBDII code B3033 mean?

B3033 indicates that the vehicleâ€™s security system has detected a potential tamper or unauthorized access attempt.

2. What are the common symptoms of the B3033 code?

Symptoms may include the security light staying on, the vehicle failing to start, or the vehicle entering anti-theft mode.

3. What causes the B3033 code to appear?

This code can be triggered by a failed ignition key or key fob, a malfunction in the security system module, or wiring issues related to the anti-theft system.

4. Can a dead key fob battery cause the B3033 code?

Yes, a dead or malfunctioning key fob can trigger the code if the vehicleâ€™s security system cannot authenticate the key.

5. How is the B3033 code diagnosed?

A technician will inspect the key, key fob, and security system module, check for damaged wiring, and use a scan tool to analyze live data and stored codes.

6. Can I clear the B3033 code without fixing the issue?

Clearing the code without addressing the underlying problem is not recommended, as the issue may persist or worsen.

7. Is the B3033 code specific to certain car brands?

This code is most commonly associated with General Motors (GM) vehicles but can appear in other makes with similar security systems.

8. Can the B3033 code prevent my car from starting?

Yes, if the anti-theft system is engaged, it may disable the engine, preventing the car from starting.

9. How much does it cost to repair the B3033 code?

Repair costs can vary widely, ranging from $50 for a new key fob battery to several hundred dollars for module reprogramming or replacement.

10. Can I fix the B3033 code myself?

Basic fixes like replacing a key fob battery or checking for loose connections can be done at home, but more complex repairs may require professional assistance.