AutoCodes – GMC – B3884 2018 GMC Sierra

B3884 2018 GMC Sierra Code - Center High Mounted Stop Lamp Circuit

Quick Answer

The brake pedal position sensor is used to sense the action of the driver's application of the brake pedal. Common causes include Faulty Center High Mounted Stop Lamp, Center High Mounted Stop Lamp harness is open or shorted, Center High Mounted Stop Lamp 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: B3884 2018 GMC Sierra indicates Center High Mounted Stop Lamp Circuit.
Common causes: Common causes include Faulty Center High Mounted Stop Lamp, Center High Mounted Stop Lamp harness is open or shorted, Center High Mounted Stop Lamp 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 170

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 Jun 16, 2023

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code B3884 2018 GMC Sierra Description

The brake pedal position sensor is used to sense the action of the driver's application of the brake pedal. The brake pedal position sensor provides an analog voltage signal that will increase as the brake pedal is applied. The Body Control Module (BCM) provides a low reference signal and a 5 V reference voltage to the brake pedal position sensor. When the variable signal reaches a voltage threshold indicating the brakes have been applied, the BCM energizes the stop lamp relay by applying a voltage to the stop lamp relay control circuit. When the stop lamp relay is energized, the relay switch contacts close, and battery voltage is applied to the Center High Mounted Stop Lamp (CHMSL) control circuit which illuminates the CHMSL. The Diagnostic Trouble Code (DTC) will be set when the BCM detects a malfunction in the stop lamp relay control circuit.

OBDII Code B3884 2018 GMC Sierra - Center High Mounted Stop Lamp Circuit - AutoCodes.com — B3884 2018 GMC Sierra Code - Center High Mounted Stop Lamp Circuit

What does this mean?

What are the Possible Causes of the DTC B3884 2018 GMC Sierra?

Faulty Center High Mounted Stop Lamp
Center High Mounted Stop Lamp harness is open or shorted
Center High Mounted Stop Lamp circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B3884 2018 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 does this mean?

Code Tech Notes

B3884:01 Center High Mounted Stop Lamp Circuit Short to Battery
B3884:02 Center High Mounted Stop Lamp Circuit Short to Ground
B3884:04 Center High Mounted Stop Lamp Circuit Open

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B3884 2018 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 B3884 2018 GMC Sierra code?

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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 B3884 2018 GMC Sierra Code

1. What does OBDII code B3884 for a 2018 GMC Sierra mean?

Code B3884 indicates a problem with the Center High Mounted Stop Lamp Circuit.

2. What are the common symptoms of OBDII code B3884 in a 2018 GMC Sierra?

Common symptoms include the center high mounted stop lamp not functioning properly or not illuminating at all.

3. What are the possible causes of OBDII code B3884 in a 2018 GMC Sierra?

Potential causes include a faulty center high mounted stop lamp, damaged wiring or connectors, or a problem with the stop lamp circuit.

4. How can I diagnose the issue related to OBDII code B3884 in my 2018 GMC Sierra?

You can start by visually inspecting the center high mounted stop lamp, checking the wiring and connectors for any damage, and using a multimeter to test the circuit for continuity.

5. Can I still drive my 2018 GMC Sierra with OBDII code B3884 present?

While the vehicle may still be drivable, it is important to address the issue promptly to ensure the center high mounted stop lamp functions correctly for safety reasons.

6. How can I repair OBDII code B3884 in a 2018 GMC Sierra?

Repair options include replacing the faulty center high mounted stop lamp, repairing any damaged wiring or connectors, or addressing any issues with the stop lamp circuit.

7. Can I reset OBDII code B3884 in my 2018 GMC Sierra without fixing the underlying issue?

Resetting the code without fixing the problem may temporarily turn off the check engine light, but the issue will likely resurface until the root cause is addressed.

8. Can a DIY enthusiast fix OBDII code B3884 in a 2018 GMC Sierra?

DIY enthusiasts with knowledge of automotive electrical systems may be able to diagnose and repair the issue, but if in doubt, it is recommended to seek professional help.

9. How much does it typically cost to repair OBDII code B3884 in a 2018 GMC Sierra?

The cost of repair can vary depending on the specific cause of the issue, but it may include the price of a new center high mounted stop lamp, wiring repairs, and labor costs.

10. Is OBDII code B3884 a common problem in 2018 GMC Sierra vehicles?

While the frequency of this specific code may vary, issues related to the center high mounted stop lamp circuit can occur in any vehicle, including the 2018 GMC Sierra.