AutoCodes – GMC – B1845 2018 GMC Sierra

B1845 2018 GMC Sierra Code - Driver Seat Lumbar Down Switch Circuit

Quick Answer

The Seat Memory Control Module supplies a reference voltage to each signal circuit of the Driver Seat Adjuster Switch. Common causes include Faulty Driver Seat Adjuster Switch, Driver Seat Adjuster Switch harness is open or shorted, Driver Seat Adjuster 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: B1845 2018 GMC Sierra indicates Driver Seat Lumbar Down Switch Circuit.
Common causes: Common causes include Faulty Driver Seat Adjuster Switch, Driver Seat Adjuster Switch harness is open or shorted, Driver Seat Adjuster 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 152

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 24, 2023

Description
Possible Causes
How To Fix
Tech Notes ▶
Cost to Diagnose
FAQs
Comments
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Code B1845 2018 GMC Sierra Description

The Seat Memory Control Module supplies a reference voltage to each signal circuit of the Driver Seat Adjuster Switch. When the power seat or lumbar switches are pressed, the appropriate signal circuit from the Seat Memory Control Module is pulled low through the switch contacts indicating the power seat command. The Seat Memory Control Module then commands the driver seat or lumbar to move in response to the switch signals. The Diagnostic Trouble Code (DTC) will be set when there is a short to ground on a switch signal circuit.

OBDII Code B1845 2018 GMC Sierra - Driver Seat Lumbar Down Switch Circuit - AutoCodes.com — B1845 2018 GMC Sierra Code - Driver Seat Lumbar Down Switch Circuit

What does this mean?

What are the Possible Causes of the DTC B1845 2018 GMC Sierra?

Faulty Driver Seat Adjuster Switch
Driver Seat Adjuster Switch harness is open or shorted
Driver Seat Adjuster Switch circuit poor electrical connection
Faulty Seat Memory Control Module

How to Fix the DTC B1845 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

User Submitted Video

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B1845 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.

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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 B1845 2018 GMC Sierra Code

1. What does OBDII code B1845 for a 2018 GMC Sierra mean?

The code B1845 specifically relates to the Driver Seat Lumbar Down Switch Circuit in the vehicle.

2. What are the common symptoms of OBDII code B1845 in a 2018 GMC Sierra?

Common symptoms may include the driver seat lumbar down switch not functioning properly, the lumbar support not adjusting as expected, or an illuminated warning light on the dashboard.

3. What are the possible causes of OBDII code B1845 in a 2018 GMC Sierra?

Potential causes of this code may include a faulty driver seat lumbar down switch, wiring issues in the circuit, a blown fuse, or a malfunction in the seat control module.

4. How can I diagnose the OBDII code B1845 in my 2018 GMC Sierra?

Diagnosis typically involves inspecting the driver seat lumbar down switch and its wiring for any visible damage, checking the fuse related to the circuit, and using a diagnostic scanner to retrieve specific error codes.

5. Can I repair OBDII code B1845 in my 2018 GMC Sierra myself?

Depending on your level of automotive expertise, you may be able to repair the issue yourself by replacing the faulty lumbar switch, repairing damaged wiring, or addressing any other identified component failures.

6. Is it safe to continue driving with OBDII code B1845 present in a 2018 GMC Sierra?

While the vehicle may still be operable with this code, it is advisable to address the underlying issue promptly to avoid potential discomfort or inconvenience from a malfunctioning driver seat lumbar support.

7. How much does it typically cost to repair OBDII code B1845 in a 2018 GMC Sierra?

The cost of repairs can vary depending on the exact cause of the issue and whether you choose to fix it yourself or seek professional assistance. Costs may include parts and labor charges.

8. Are there any preventive measures to avoid OBDII code B1845 in a 2018 GMC Sierra?

Regularly inspecting and maintaining the driver seat lumbar support system, avoiding excessive force when adjusting the lumbar support, and promptly addressing any related issues can help prevent the occurrence of this fault code.

9. Can a DIY enthusiast reset OBDII code B1845 in a 2018 GMC Sierra without professional help?

Resetting the code can be done using an OBDII scanner to clear the error code. However, it is recommended to first diagnose and address the root cause of the issue to prevent the code from reappearing.

10. How long does it typically take to repair OBDII code B1845 in a 2018 GMC Sierra?

The repair time can vary based on the complexity of the issue and the repair approach taken. Simple fixes like replacing a switch may take a short time, while more intricate problems could require more extensive troubleshooting and repair work.