AutoCodes – Generic – B051A:02

B051A:02 Code - Left Side Assist Step Motor Control Circuit Short to Ground

Quick Answer

The Assist Step Control (ASC) Module controls the running board actuators to extend or retract the running boards. Common causes include Faulty Left Side Assist Step Motor, Left Side Assist Step Motor harness is open or shorted, Left Side Assist Step Motor circuit poor electrical connection. Severity is Low - monitor the vehicle and repair when practical. The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.

What it means: B051A:02 indicates Left Side Assist Step Motor Control Circuit Short to Ground.
Common causes: Common causes include Faulty Left Side Assist Step Motor, Left Side Assist Step Motor harness is open or shorted, Left Side Assist Step Motor circuit poor electrical connection.
Severity: Low - monitor the vehicle and repair when practical.
Can I drive?: The vehicle can usually be driven if no severe symptoms are present, but symptoms should be checked before extended driving.

Save to My Repairs My Repairs

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

Code Popularity 301

How popular is this code, among other codes? Low

Repair Importance Level

Low (Monitor) (1 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Nov 13, 2022

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 B051A:02 Description

The Assist Step Control (ASC) Module controls the running board actuators to extend or retract the running boards. Each actuator consists of an electric motor and a potentiometer. The module supplies a low reference and 10-volt reference source voltage to the potentiometer. The ASC control module monitors the voltage drop across the potentiometer on the position signal circuit. When the actuator shaft rotates, the voltage on the position signal circuit changes. The ASC control module supplies the actuator motor with a 12-volt control circuit and a ground control circuit. The ASC module controls the direction of the actuator by changing the polarity of the control circuits. The Diagnostic Trouble Code (DTC) will be set when a motor control circuit is shorted to ground.

OBDII Code B051A:02 - Left Side Assist Step Motor Control Circuit Short to Ground - AutoCodes.com — B051A:02 Code - Left Side Assist Step Motor Control Circuit Short to Ground

What does this mean?

What are the Possible Causes of the DTC B051A:02?

Faulty Left Side Assist Step Motor
Left Side Assist Step Motor harness is open or shorted
Left Side Assist Step Motor circuit poor electrical connection
Faulty Assist Step Control (ASC) Module

How to Fix the DTC B051A:02?

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

B051A:0B Left Side Assist Step Motor Control Circuit Current Above Threshold
B051A:01 Left Side Assist Step Motor Control Circuit Short to Battery
B051A:02 Left Side Assist Step Motor Control Circuit Short to Ground
B051A:04 Left Side Assist Step Motor Control Circuit Open Circuit

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the B051A:02 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 B051A:02 code?

Need more information on how to fix the B051A:02 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the B051A:02 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 B051A:02 Code

1. What does the OBDII code B051A:02 mean?

The code B051A:02 indicates a "Left Side Assist Step Motor Control Circuit Short to Ground," meaning there's an electrical issue in the circuit controlling the left side assist step motor.

2. What are the common symptoms of the B051A:02 code?

Typical symptoms include the left side assist step not deploying or retracting, intermittent operation, or a warning light on the dashboard.

3. What causes the B051A:02 code to appear?

This code is usually caused by damaged wiring, a short to ground in the control circuit, a faulty assist step motor, or a malfunctioning control module.

4. Can I still drive my vehicle if the B051A:02 code is present?

Yes, you can drive the vehicle, but the left side assist step may not function properly, which could be inconvenient or pose a safety hazard when entering or exiting the vehicle.

5. How do I diagnose the B051A:02 code?

Start by inspecting the wiring and connectors for damage or corrosion. Use a multimeter to test for a short to ground and verify the integrity of the assist step motor and the control module.

6. What tools are needed to fix the B051A:02 code?

Youâ€™ll need basic tools like a multimeter, wire repair kit, and possibly a scan tool to clear the code after repairs are completed.

7. Can a blown fuse cause the B051A:02 code?

Yes, a blown fuse related to the assist step motor circuit can cause this code, as it might indicate a short to ground.

8. How much does it cost to fix the B051A:02 code?

Repair costs vary, but fixing damaged wiring or replacing the assist step motor may cost anywhere from $100 to $500, depending on labor and parts.

9. Can I fix the B051A:02 code myself?

If you have basic electrical knowledge and tools, you can attempt to repair wiring or replace components. However, complex electrical issues may require professional assistance.

10. Will clearing the B051A:02 code fix the problem permanently?

No, clearing the code without addressing the underlying issue will only temporarily remove the fault. The code will return if the problem persists.