AutoCodes – GMC – B2605 2018 GMC Sierra

B2605 2018 GMC Sierra Code - Right Daytime Running Lamps Control Circuit

Quick Answer

The ambient light sensor is used to monitor outside lighting conditions. Common causes include Faulty Right Headlamp Assembly, Right Headlamp Assembly harness is open or shorted, Right 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: B2605 2018 GMC Sierra indicates Right Daytime Running Lamps Control Circuit.
Common causes: Common causes include Faulty Right Headlamp Assembly, Right Headlamp Assembly harness is open or shorted, Right 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 162

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 B2605 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 B2605 2018 GMC Sierra - Right Daytime Running Lamps Control Circuit - AutoCodes.com — B2605 2018 GMC Sierra Code - Right Daytime Running Lamps Control Circuit

What does this mean?

What are the Possible Causes of the DTC B2605 2018 GMC Sierra?

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

How to Fix the DTC B2605 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

B2605:01 Right Daytime Running Lamps Control Circuit short to Battery
B2605:02 Right Daytime Running Lamps Control Circuit Short to Ground
B2605:04 Right Daytime Running Lamps Control Circuit Open

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B2605 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 B2605 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 B2605 2018 GMC Sierra Code

1. What are the common symptoms of OBDII code B2605 in a 2018 GMC Sierra related to the Right Daytime Running Lamps Control Circuit?

- The common symptoms include the right daytime running lamp not working, flickering, or staying on constantly.

2. What are the possible causes of OBDII code B2605 in a 2018 GMC Sierra?

- The possible causes could be a faulty daytime running lamp, damaged wiring or connectors, a defective control module, or a blown fuse.

3. How can I diagnose the Right Daytime Running Lamps Control Circuit issue in my 2018 GMC Sierra?

- You can start by visually inspecting the wiring and connectors for any visible damage. Using a multimeter, check for continuity and voltage at different points in the circuit.

4. Can I repair OBDII code B2605 in my 2018 GMC Sierra myself?

- If you have experience with automotive electrical systems, you may be able to repair the issue yourself by identifying the faulty component and replacing it. However, professional help may be required for complex diagnoses.

5. Is it safe to continue driving my 2018 GMC Sierra with OBDII code B2605 unresolved?

- While the vehicle may still be drivable with the right daytime running lamp not functioning properly, it is recommended to address the issue promptly to ensure proper visibility and safety on the road.

6. How much does it typically cost to repair OBDII code B2605 in a 2018 GMC Sierra at a dealership or repair shop?

- The cost of repair can vary depending on the specific cause of the issue and the labor rates of the service provider. It's recommended to obtain a few quotes for an accurate estimate.

7. Can extreme weather conditions affect the Right Daytime Running Lamps Control Circuit in a 2018 GMC Sierra?

- Yes, extreme weather conditions such as moisture or extreme temperatures can potentially damage the wiring or components involved in the daytime running lamp circuit.

8. Will resetting the OBDII code B2605 in my 2018 GMC Sierra make the issue go away permanently?

- Resetting the code may temporarily turn off the warning light, but if the underlying issue causing the code is not fixed, it is likely to reoccur.

9. Are there any recalls or technical service bulletins related to OBDII code B2605 for the 2018 GMC Sierra?

- It's recommended to check with a GMC dealership or online resources for any relevant recalls or technical service bulletins related to this specific OBDII code.

10. Can a weak car battery cause OBDII code B2605 to trigger in a 2018 GMC Sierra?

- While a weak car battery may not directly cause this specific code, electrical issues stemming from a weak battery can potentially lead to malfunctions in the Right Daytime Running Lamps Control Circuit.