AutoCodes – Cadillac – B3920 Cadillac

B3920 Cadillac Code - Seat Motors Group 1 Common Circuit

Quick Answer

The Seat Memory Control Module controls the seat, lumbar, and adjustable pedal motors via half bridges that are connected to power rails internal to the module. Common causes include Faulty Seat, Lumbar, or Adjustable Pedal Motors, Seat, Lumbar, or Adjustable Pedal Motors harness is open or shorted, Seat, Lumbar, or Adjustable Pedal Motors 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: B3920 Cadillac indicates Seat Motors Group 1 Common Circuit.
Common causes: Common causes include Faulty Seat, Lumbar, or Adjustable Pedal Motors, Seat, Lumbar, or Adjustable Pedal Motors harness is open or shorted, Seat, Lumbar, or Adjustable Pedal Motors 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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 1,667

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 16, 2023

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code B3920 Cadillac Description

The Seat Memory Control Module controls the seat, lumbar, and adjustable pedal motors via half bridges that are connected to power rails internal to the module. The Seat Memory Control Module connects all of the motor control circuits on each power rail to a common reference point whenever they are not in operation. The module monitors all seat motor control circuits for a shorted to ground or voltage before enabling any seat motor.
When a power seat, lumbar, or adjustable pedal switch is pressed or when a memory recall is requested, each seat motor receives battery voltage and ground from the seat memory control module via the motor control circuits. All motors are reversible, so the direction the motor rotates depends on which control circuit voltage is applied and which control circuit ground is applied. When the switch is operated in the opposite direction, the module reverses the polarity and applies voltage and ground to the opposite circuits to move the seat in the opposite direction.
The Diagnostic Trouble Code (DTC) sets when the voltage on any power rail 1 motor control circuit exceeds 2.78 volts for 100 ms or is below 1.47 volts for 100 ms.

OBDII Code B3920 Cadillac - Seat Motors Group 1 Common Circuit - AutoCodes.com — B3920 Cadillac Code - Seat Motors Group 1 Common Circuit

What does this mean?

What are the Possible Causes of the DTC B3920 Cadillac?

Faulty Seat, Lumbar, or Adjustable Pedal Motors
Seat, Lumbar, or Adjustable Pedal Motors harness is open or shorted
Seat, Lumbar, or Adjustable Pedal Motors circuit poor electrical connection
Faulty Seat Memory Control Module

How to Fix the DTC B3920 Cadillac?

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

B3920 01 Group 1 Seat Motors Circuit Shorted to Battery or Open
B3920 02 Group 1 Seat Motors Circuit Shorted to Ground

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B3920 Cadillac 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 B3920 Cadillac code?

Need more information on how to fix the B3920 Cadillac code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B3920 Cadillac code diagnosed by a professional: Find a repair shop in your area

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 B3920 Cadillac Code

1. What are the common symptoms of OBDII code B3920 in a Cadillac related to the Seat Motors Group 1 Common Circuit?

- Common symptoms include inoperative seat adjustment functions, such as the inability to move the seat forward, backward, up, or down.

2. What are the possible causes of OBDII code B3920 in a Cadillac?

- The code B3920 in a Cadillac is typically caused by a malfunction in the common circuit of the seat motors group 1, which can be due to wiring issues, a faulty control module, or a defective motor.

3. How can I diagnose the OBDII code B3920 in my Cadillac related to the Seat Motors Group 1 Common Circuit?

- Diagnosis usually involves inspecting the wiring harness for any damage, checking the seat motor connections, and using a diagnostic scanner to retrieve the specific fault codes.

4. Can I fix the OBDII code B3920 in my Cadillac at home?

- Depending on your level of expertise, you may be able to fix the issue at home by checking and repairing any damaged wiring, replacing a faulty motor, or resetting the control module. However, some cases may require professional assistance.

5. Are there any repair tips for addressing OBDII code B3920 in a Cadillac?

- It's recommended to start by checking the wiring harness and connectors for any signs of damage or corrosion. Additionally, resetting the control module and conducting a thorough inspection of the seat motors can help resolve the issue.

6. What are the potential risks of ignoring OBDII code B3920 in a Cadillac?

- Ignoring the B3920 code related to the Seat Motors Group 1 Common Circuit in a Cadillac can lead to continued seat adjustment problems, discomfort while driving, and potential safety hazards if the seat cannot be properly adjusted.

7. How do I clear the OBDII code B3920 from my Cadillac's system after making repairs?

- After addressing the underlying issue causing the B3920 code, you can use an OBDII scanner to clear the code from the system. This will reset the check engine light and allow you to monitor if the problem reoccurs.

8. Is it safe to drive my Cadillac with the OBDII code B3920 present?

- It is generally safe to drive your Cadillac with the B3920 code related to the Seat Motors Group 1 Common Circuit, but it is advisable to address the issue promptly to avoid any inconvenience or discomfort while driving.

9. How much does it typically cost to repair OBDII code B3920 in a Cadillac at a dealership or repair shop?

- The cost of repairing the B3920 code in a Cadillac can vary depending on the underlying cause of the issue, but it may involve expenses for parts replacement, labor, and diagnostic services. It's recommended to inquire with a dealership or repair shop for an accurate estimate.

10. Are there any recalls or technical service bulletins related to OBDII code B3920 in Cadillac vehicles?

- It's advisable to check with a Cadillac dealership or visit the manufacturer's website to see if there are any recalls or technical service bulletins related to the B3920 code in your specific Cadillac model.