AutoCodes – GMC – B133B 2015 GMC Sierra

B133B 2015 GMC Sierra Code - Reverse Gear Status Not Plausible

Quick Answer

The Human Machine Interface Control Module receives a signal from the Human Machine Interface Control Module Bypass Module indicating reverse gear status. Common causes include Faulty Body Control Module (BCM), Body Control Module harness is open or shorted, Body Control Module 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: B133B 2015 GMC Sierra indicates Reverse Gear Status Not Plausible.
Common causes: Common causes include Faulty Body Control Module (BCM), Body Control Module harness is open or shorted, Body Control Module 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 178

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 17, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code B133B 2015 GMC Sierra Description

The Human Machine Interface Control Module receives a signal from the Human Machine Interface Control Module Bypass Module indicating reverse gear status. The reverse gear status is used to determine when to activate the rearview camera display. The Human Machine Interface Control Module also receives another reverse gear status message via serial data. The Human Machine Interface Control Module compares the two serial data messages to verify the plausibility of the messages. The Diagnostic Trouble Code (DTC) will be set when the Human Machine Interface Control Module has determined the reverse message states do not match and are therefore not plausible.

OBDII Code B133B 2015 GMC Sierra - Reverse Gear Status Not Plausible - AutoCodes.com — B133B 2015 GMC Sierra Code - Reverse Gear Status Not Plausible

What does this mean?

What are the Possible Causes of the DTC B133B 2015 GMC Sierra?

Faulty Body Control Module (BCM)
Body Control Module harness is open or shorted
Body Control Module circuit poor electrical connection
Faulty Human Machine Interface Control Module

How to Fix the DTC B133B 2015 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 B133B 2015 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 B133B 2015 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 B133B 2015 GMC Sierra Code

1. What does the OBDII code B133B mean on a 2015 GMC Sierra?

B133B indicates a "Reverse Gear Status Not Plausible" fault, meaning the vehicle's control module has detected an issue with the reverse gear signal or its plausibility.

2. What are the common symptoms of the B133B code?

Symptoms may include the reverse gear not engaging, malfunction of the reverse lights, or a "Check Engine" or other warning light on the dashboard.

3. What causes the B133B code to appear?

Common causes include faulty transmission range sensors, damaged wiring or connectors in the reverse gear circuit, or a malfunctioning transmission control module (TCM).

4. Can a faulty shifter cause the B133B code?

Yes, a faulty gear shifter or its position sensor can cause the reverse gear status to be read as implausible.

5. How can I diagnose the B133B code?

Start by checking the transmission range sensor, inspecting wiring and connectors for damage, and using a scan tool to monitor the reverse gear position signal.

6. Is the B133B code serious?

It can be serious if the reverse gear fails to engage, which may affect drivability and safety. Prompt diagnosis and repair are recommended.

7. Can I fix the B133B code myself?

If you're comfortable with basic diagnostics, you can inspect the wiring, connectors, and transmission range sensor. However, more complex repairs may require professional help.

8. How much does it cost to repair the B133B code?

Repair costs vary depending on the issue. Replacing a transmission range sensor may cost $150â€“$300, while complex wiring repairs or TCM replacement can cost more.

9. Will clearing the B133B code fix the problem?

Clearing the code without addressing the root cause will only temporarily remove the warning. The code will likely return until the issue is resolved.

10. Can a low battery cause the B133B code?

In some cases, a weak or failing battery may cause erratic signals in the transmission system, potentially triggering the code. Always ensure the battery is in good condition.