AutoCodes – GMC – P18BE 2016 GMC Sierra

P18BE 2016 GMC Sierra Code - Internal Mode Switch 'S' Circuit Stuck Off Invalid Voltage Range

Quick Answer

The internal mode switch indicates the Transmission Control Module (TCM) which gear position the vehicle operator has selected. Common causes include Faulty Transmission Internal Mode Switch, Transmission Internal Mode Switch harness is open or shorted, Transmission Internal Mode 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: P18BE 2016 GMC Sierra indicates Internal Mode Switch 'S' Circuit Stuck Off Invalid Voltage Range.
Common causes: Common causes include Faulty Transmission Internal Mode Switch, Transmission Internal Mode Switch harness is open or shorted, Transmission Internal Mode 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 260

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 Mar 23, 2024

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P18BE 2016 GMC Sierra Description

The internal mode switch indicates the Transmission Control Module (TCM) which gear position the vehicle operator has selected. The internal mode switch consists of 5 separate hall effect switches. Each hall effect switch is supplied with a 9 V reference circuit and a signal circuit from the TCM. Each signal circuit for each gear selector position will have either a voltage reading of 0.70–0.96 V indicating On or 1.68–2.38 V indicating Off. The voltage values on each internal mode switch circuit will change and are dependent on the position of the gear selector. The state of each internal mode switch A/B/C/P/S signal circuit is displayed on the scan tool. The Diagnostic Trouble Code (DTC) will be set when the TCM has detected the internal mode switch S signal circuit has an invalid voltage range of 1.68 – 2.38 V, for 2.7 s.

OBDII Code P18BE 2016 GMC Sierra - Internal Mode Switch 'S' Circuit Stuck Off Invalid Voltage Range - AutoCodes.com — P18BE 2016 GMC Sierra Code - Internal Mode Switch 'S' Circuit Stuck Off Invalid Voltage Range

What does this mean?

What are the Possible Causes of the DTC P18BE 2016 GMC Sierra?

Faulty Transmission Internal Mode Switch
Transmission Internal Mode Switch harness is open or shorted
Transmission Internal Mode Switch circuit poor electrical connection
Faulty Transmission Control Module (TCM)

How to Fix the DTC P18BE 2016 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 P18BE 2016 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 P18BE 2016 GMC Sierra code?

Need more information on how to fix the P18BE 2016 GMC Sierra code? Get Access to Factory Service Manuals

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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 P18BE 2016 GMC Sierra Code

1. What are the common symptoms of OBDII code P18BE in a 2016 GMC Sierra?

The common symptoms of OBDII code P18BE include issues with shifting gears, transmission problems, and the inability to switch between different driving modes.

2. What can cause the Internal Mode Switch 'S' Circuit Stuck Off Invalid Voltage Range error in a 2016 GMC Sierra?

The most common causes of the P18BE code in a 2016 GMC Sierra are a faulty internal mode switch, wiring issues, or a malfunctioning transmission control module.

3. How can I diagnose the Internal Mode Switch 'S' Circuit Stuck Off error in my 2016 GMC Sierra?

Diagnosing the P18BE code involves using a diagnostic scanner to retrieve the trouble codes, checking the internal mode switch for proper operation, and inspecting the wiring for any damage or loose connections.

4. Can I continue driving my 2016 GMC Sierra with the OBDII code P18BE?

It is not recommended to drive your vehicle with the P18BE code as it can lead to further transmission issues and potential safety hazards. It is best to address the problem promptly.

5. How can I repair the Internal Mode Switch 'S' Circuit Stuck Off error in my 2016 GMC Sierra?

Repairing the P18BE code may involve replacing the internal mode switch, repairing or replacing damaged wiring, or reprogramming the transmission control module. It is advisable to consult a professional mechanic for proper diagnosis and repair.

6. Are there any DIY tips for fixing the OBDII code P18BE in a 2016 GMC Sierra?

While some simple checks like inspecting the wiring for visible damage can be done by DIY enthusiasts, repairing the P18BE code often requires specialized tools and expertise. It is recommended to seek professional help for accurate diagnosis and repair.

7. How much does it cost to fix the Internal Mode Switch 'S' Circuit Stuck Off error in a 2016 GMC Sierra?

The cost of fixing the P18BE code can vary depending on the exact cause of the issue, the labor rates in your area, and the cost of replacement parts. It is advisable to get quotes from different mechanics to compare prices.

8. Can a faulty internal mode switch cause other problems in a 2016 GMC Sierra?

Yes, a faulty internal mode switch can cause various transmission-related issues, affect the overall performance of the vehicle, and trigger additional trouble codes in the system.

9. Is the OBDII code P18BE a common issue in 2016 GMC Sierra vehicles?

While the P18BE code may not be extremely common, some 2016 GMC Sierra owners have reported experiencing this issue. Regular maintenance and prompt repairs can help prevent such problems.

10. How long does it typically take to repair the Internal Mode Switch 'S' Circuit Stuck Off error in a 2016 GMC Sierra?

The repair time for the P18BE code can vary based on the exact cause of the issue, the availability of parts, and the mechanic's workload. In general, it may take a few hours to a full day to diagnose and fix the problem.