AutoCodes – GMC – B2600 2018 GMC Sierra

B2600 2018 GMC Sierra Code - Left Daytime Running Lamps Control Circuit

Quick Answer

The ambient light sensor is used to monitor outside lighting conditions. Common causes include Faulty Left Headlamp Assembly, Left Headlamp Assembly harness is open or shorted, Left Headlamp Assembly 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: B2600 2018 GMC Sierra indicates Left Daytime Running Lamps Control Circuit.
Common causes: Common causes include Faulty Left Headlamp Assembly, Left Headlamp Assembly harness is open or shorted, Left Headlamp Assembly 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 237

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 May 26, 2023

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code B2600 2018 GMC Sierra Description

The ambient light sensor is used to monitor outside lighting conditions. The ambient light sensor provides a voltage signal that will vary between 0.2 and 4.9 volts depending on outside lighting conditions. The Body Control Module (BCM) provides a 5-volt reference signal to the ambient light sensor and the Heating, Ventilation, and Air Conditioning (HVAC) control module provides a low reference ground. The BCM monitors the ambient light sensor signal circuit to determine if outside lighting conditions are correct for either Daytime Running Lights (DRL) or Automatic Lamp Control (ALC) when the headlamp switch is in the AUTO position. In daylight conditions, the BCM will command the DRLs ON. During low light conditions, the BCM will command the low beam headlamps ON. Any function or condition that turns on the headlamps will cancel the DRL operation. The Diagnostic Trouble Code (DTC) will be set when the BCM detects a problem in the left DRL control circuit.

OBDII Code B2600 2018 GMC Sierra - Left Daytime Running Lamps Control Circuit - AutoCodes.com — B2600 2018 GMC Sierra Code - Left Daytime Running Lamps Control Circuit

What does this mean?

What are the Possible Causes of the DTC B2600 2018 GMC Sierra?

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

How to Fix the DTC B2600 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

B2600:01 Left Daytime Running Lamps Control Circuit short to Battery
B2600:02 Left Daytime Running Lamps Control Circuit Short to Ground
B2600:04 Left Daytime Running Lamps Control Circuit Open

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B2600 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 B2600 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 B2600 2018 GMC Sierra Code

1. What does the OBDII code B2600 mean on a 2018 GMC Sierra?

B2600 indicates an issue with the Left Daytime Running Lamps (DRL) Control Circuit, which means thereâ€™s a malfunction in the electrical circuit controlling the left DRL.

2. What are the symptoms of code B2600 on a 2018 GMC Sierra?

Common symptoms include the left daytime running lamp not working, a warning light on the dashboard, or intermittent operation of the left DRL.

3. What causes the B2600 code to trigger on a 2018 GMC Sierra?

Possible causes include a faulty left DRL bulb, damaged wiring or connectors, a malfunctioning DRL control module, or a blown fuse.

4. Can a bad DRL bulb cause code B2600 on a GMC Sierra?

Yes, a burned-out or faulty left DRL bulb is one of the most common causes of this code.

5. How can I fix the B2600 code on my 2018 GMC Sierra?

Inspect and replace the left DRL bulb if necessary, check all wiring and connectors for damage or corrosion, and verify that the fuse and DRL control module are functioning properly.

6. Is it safe to drive with the B2600 code on a GMC Sierra?

Yes, it is generally safe to drive, but the left daytime running lamp may not function, reducing visibility to other drivers during daylight hours.

7. How do I diagnose the cause of the B2600 code on a 2018 GMC Sierra?

Use a multimeter to test the DRL circuit for continuity, inspect the bulb and connectors for damage, and check for power at the left DRL socket.

8. What tools are needed to repair a B2600 code on a GMC Sierra?

You may need a multimeter, replacement DRL bulb, wiring repair tools, and possibly a diagnostic scan tool to clear the code after repairs.

9. Can the B2600 code on a GMC Sierra be cleared without repairs?

Clearing the code without addressing the underlying issue may temporarily remove it, but it will likely return once the vehicle detects the problem again.

10. How much does it typically cost to fix the B2600 code on a 2018 GMC Sierra?

Repair costs can range from $10 for a new bulb to $200 or more if wiring or the control module needs replacement. Labor costs may vary depending on the complexity of the repair.