AutoCodes – GMC – B243A 2018 GMC Sierra

B243A 2018 GMC Sierra Code - Left Front Seat Heating Switch

Quick Answer

The Body Control Module (BCM) detects an internal fault with the seat heating switch. Common causes include Faulty Left Front Seat Heating Switch, Left Front Seat Heating Switch harness is open or shorted, Left Front Seat Heating 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: B243A 2018 GMC Sierra indicates Left Front Seat Heating Switch.
Common causes: Common causes include Faulty Left Front Seat Heating Switch, Left Front Seat Heating Switch harness is open or shorted, Left Front Seat Heating 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 141

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 Apr 26, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B243A 2018 GMC Sierra Description

The Body Control Module (BCM) detects an internal fault with the seat heating switch. No external circuits are involved. The Diagnostic Trouble Code (DTC) sets when the BCM detects an internal fault with the seat heating switch.

OBDII Code B243A 2018 GMC Sierra - Left Front Seat Heating Switch - AutoCodes.com — B243A 2018 GMC Sierra Code - Left Front Seat Heating Switch

What does this mean?

What are the Possible Causes of the DTC B243A 2018 GMC Sierra?

Faulty Left Front Seat Heating Switch
Left Front Seat Heating Switch harness is open or shorted
Left Front Seat Heating Switch circuit poor electrical connection
Faulty Body Control Module (BCM)

How to Fix the DTC B243A 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 is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B243A 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 B243A 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 B243A 2018 GMC Sierra Code

1. What does the OBDII code B243A mean on a 2018 GMC Sierra?

The code B243A indicates an issue with the Left Front Seat Heating Switch, typically related to a malfunction in the switch's electrical circuit.

2. What are the common symptoms of the B243A code?

Symptoms include the left front seat heater not working, erratic seat heating behavior, or the seat heater switch not lighting up.

3. What causes the B243A code to appear?

Common causes include a faulty seat heating switch, damaged wiring or connectors, or a malfunctioning seat control module.

4. Can I still drive my 2018 GMC Sierra with the B243A code active?

Yes, the truck is safe to drive, but the left front seat heater functionality will likely be impaired.

5. How do I diagnose the B243A code?

Check the seat heating switch for physical damage, inspect the wiring and connectors for corrosion or breaks, and use a scan tool to verify the code and monitor the switch's electrical signals.

6. How can I fix the B243A code on my 2018 GMC Sierra?

Repairs may include replacing the seat heating switch, repairing damaged wiring, or recalibrating or replacing the seat control module.

7. How much does it cost to fix the B243A code?

The repair cost can range from $50 for a simple switch replacement to $300 or more if wiring or the seat control module needs repair or replacement.

8. Can a blown fuse cause the B243A code?

While uncommon, a blown fuse in the seat heating circuit could cause the code. Inspect and replace any blown fuses if necessary.

9. Does the B243A code require professional repair?

If you're comfortable with basic electrical diagnostics, you can inspect and replace the switch or wiring yourself. Otherwise, a professional mechanic is recommended.

10. Will clearing the B243A code fix the issue?

Clearing the code may temporarily remove the warning, but the underlying issue must be addressed to prevent it from returning.