AutoCodes – Chevrolet – B2740 2016 Chevrolet Silverado

B2740 2016 Chevrolet Silverado Code - Front Fog Lamp Switch Circuit Malfunction

Quick Answer

The front fog lamp relay is supplied with battery voltage at all times. Common causes include Faulty Headlamp Switch, Headlamp Switch harness is open or shorted, Headlamp Switch 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: B2740 2016 Chevrolet Silverado indicates Front Fog Lamp Switch Circuit Malfunction.
Common causes: Common causes include Faulty Headlamp Switch, Headlamp Switch harness is open or shorted, Headlamp Switch 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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 144

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 01, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code B2740 2016 Chevrolet Silverado Description

The front fog lamp relay is supplied with battery voltage at all times. The front fog lamp switch signal circuit is grounded momentarily by pressing the front fog lamp switch. The Body Control Module (BCM) energizes the front fog lamp relay by applying ground to the front fog lamp relay control circuit. When the front fog lamp relay is energized, the relay switch contacts close, and battery voltage is applied through the fog lamp fuse to the front fog lamp control circuit which illuminates the front fog lamps. With the front fog lamp switch activated the BCM sends a message via serial data to the instrument cluster requesting the instrument cluster to illuminate the front fog indicator. The Diagnostic Trouble Code (DTC) sets when the BCM detects a short to ground in the front fog lamp switch signal circuit.

OBDII Code B2740 2016 Chevrolet Silverado - Front Fog Lamp Switch Circuit Malfunction - AutoCodes.com — B2740 2016 Chevrolet Silverado Code - Front Fog Lamp Switch Circuit Malfunction

What does this mean?

What are the Possible Causes of the DTC B2740 2016 Chevrolet Silverado?

Faulty Headlamp Switch
Headlamp Switch harness is open or shorted
Headlamp Switch circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B2740 2016 Chevrolet Silverado?

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 B2740 2016 Chevrolet Silverado 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 B2740 2016 Chevrolet Silverado code?

Need more information on how to fix the B2740 2016 Chevrolet Silverado code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B2740 2016 Chevrolet Silverado code diagnosed by a professional: Find a repair shop in your area

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 B2740 2016 Chevrolet Silverado Code

1. What does the OBDII code B2740 mean on a 2016 Chevrolet Silverado?

The code B2740 indicates a Front Fog Lamp Switch Circuit Malfunction, meaning there is an issue with the electrical circuit or components related to the fog lamp switch.

2. What are common symptoms of the B2740 code in a 2016 Chevrolet Silverado?

Symptoms may include the fog lamps not turning on, inconsistent fog lamp operation, or the fog lamp indicator on the dashboard not working correctly.

3. What causes the B2740 code to appear on a 2016 Chevrolet Silverado?

Possible causes include a faulty fog lamp switch, damaged wiring or connectors, a blown fuse, or a malfunction in the body control module (BCM).

4. Can a blown fuse trigger the B2740 code in my 2016 Silverado?

Yes, a blown fuse in the fog lamp circuit can cause this code by disrupting the electrical flow needed for the fog lamp switch to function properly.

5. How can I diagnose the B2740 code in a 2016 Chevrolet Silverado?

Start by inspecting the fog lamp switch, wiring, and connectors for damage or corrosion. Check the fuse and relay for the fog lamp circuit. Use a scan tool to monitor the switch operation and verify BCM functionality.

6. How do I fix the B2740 code on my 2016 Chevrolet Silverado?

Repairs may involve replacing the fog lamp switch, repairing or replacing damaged wiring, cleaning corroded connectors, or replacing a faulty BCM if necessary.

7. Is it safe to drive with the B2740 code on a 2016 Chevrolet Silverado?

Yes, it is generally safe to drive, but the fog lamps may not function properly, which can reduce visibility in foggy or low-light conditions.

8. Does the B2740 code mean I need to replace the fog lamp switch on my 2016 Silverado?

Not necessarily. While the switch could be faulty, the issue could also lie in the wiring, connectors, or BCM. Proper diagnosis is needed to confirm the cause.

9. Can a faulty Body Control Module (BCM) cause the B2740 code?

Yes, a malfunctioning BCM can cause this code if it fails to properly interpret or transmit signals from the fog lamp switch.

10. What tools do I need to troubleshoot the B2740 code on my 2016 Chevrolet Silverado?

Youâ€™ll need a multimeter to check electrical connections, a scan tool to read live data and confirm BCM operation, and basic hand tools to inspect and repair wiring or replace components.