AutoCodes – GMC – B3596 GMC

B3596 GMC Code - Hazard Lamps Request Circuit Malfunction

Quick Answer

The hazard flashers may be activated in any power mode. Common causes include Faulty Turn Signal/Multifunction Switch, Turn Signal/Multifunction Switch harness is open or shorted, Turn Signal/Multifunction 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: B3596 GMC indicates Hazard Lamps Request Circuit Malfunction.
Common causes: Common causes include Faulty Turn Signal/Multifunction Switch, Turn Signal/Multifunction Switch harness is open or shorted, Turn Signal/Multifunction 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.

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Code Popularity 1,096

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 13, 2023

Description
Possible Causes
How To Fix
Tech Notes ▶
Cost to Diagnose
FAQs
Comments
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Code B3596 GMC Description

The hazard flashers may be activated in any power mode. The hazard warning switch signal circuit is momentarily grounded when the hazard warning switch is pressed. The Body Control Module (BCM) responds to the hazard warning switch signal input by supplying battery voltage to all four turn signal lamps in an ON and OFF duty cycle. When the hazard warning switch is activated, the BCM sends a serial data message to the instrument cluster requesting both turn signal indicators to be cycled ON and OFF. The Diagnostic Trouble Code (DTC) sets when the BCM detects a short to ground in the hazard warning switch signal circuit.

OBDII Code B3596 GMC - Hazard Lamps Request Circuit Malfunction - AutoCodes.com — B3596 GMC Code - Hazard Lamps Request Circuit Malfunction

What does this mean?

What are the Possible Causes of the DTC B3596 GMC?

Faulty Turn Signal/Multifunction Switch
Turn Signal/Multifunction Switch harness is open or shorted
Turn Signal/Multifunction Switch circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B3596 GMC?

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

User Submitted Video

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B3596 GMC 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 B3596 GMC code?

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Need Help with the Code?

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Information for Specific GMC Models

B3596 2014 GMC Sierra — Hazard Lamps Request Circuit Malfunction
B3596 2015 GMC Sierra — Hazard Lamps Request Circuit Malfunction
B3596 2016 GMC Sierra — Hazard Lamps Request Circuit Malfunction
B3596 2017 GMC Sierra — Hazard Lamps Request Circuit Malfunction
B3596 2018 GMC Sierra — Hazard Lamps Request Circuit Malfunction

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 B3596 GMC Code

1. What are the common symptoms of OBDII code B3596 GMC (Hazard Lamps Request Circuit Malfunction)?

The common symptoms include non-functional hazard lamps, erratic blinking of hazard lights, and illumination of the check engine light.

2. What are the possible causes of OBDII code B3596 GMC?

Possible causes of this code include a faulty hazard lamp switch, damaged wiring or connectors in the hazard lamp circuit, or a defective body control module.

3. How can I diagnose the Hazard Lamps Request Circuit Malfunction in my GMC vehicle?

Diagnosing this issue typically involves using a diagnostic scanner to read the OBDII code, inspecting the hazard lamp switch and related wiring, and testing the body control module for proper functionality.

4. Can I continue driving my vehicle with OBDII code B3596 GMC active?

While the vehicle is technically safe to drive with this code, it is advisable to address the issue promptly to ensure the proper functioning of the hazard lamps in emergency situations.

5. How can I repair OBDII code B3596 GMC in my GMC vehicle?

Repairing this code may involve replacing the hazard lamp switch, repairing damaged wiring or connectors, or reprogramming the body control module. It is recommended to follow the manufacturer's repair procedures.

6. Are there any DIY tips for fixing the Hazard Lamps Request Circuit Malfunction?

If you have experience with automotive electrical systems, you may attempt to visually inspect the hazard lamp circuit for visible damage or loose connections before seeking professional assistance.

7. Is OBDII code B3596 GMC a common issue in GMC vehicles?

While this code may not be as common as some other OBDII codes, it can still occur in GMC vehicles, particularly as they age and electrical components wear out.

8. Can extreme weather conditions affect the Hazard Lamps Request Circuit Malfunction?

Extreme weather conditions can potentially impact the functioning of electrical components in the hazard lamp circuit, leading to malfunctions that trigger this OBDII code.

9. Will resetting the OBDII code B3596 GMC make it go away permanently?

Resetting the code may temporarily turn off the check engine light, but if the underlying issue causing the code is not addressed, it is likely to reoccur.

10. How much does it typically cost to repair OBDII code B3596 GMC at a mechanic or dealership?

The cost of repairing this code can vary depending on the specific issue and the labor rates of the mechanic or dealership. It is recommended to get a diagnosis and estimate before proceeding with the repair.