AutoCodes – Chevrolet – P18C3 2014 Chevrolet Silverado

P18C3 2014 Chevrolet Silverado Code - Internal Mode Switch 'S' Circuit Stuck On 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: P18C3 2014 Chevrolet Silverado indicates Internal Mode Switch 'S' Circuit Stuck On 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 259

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 P18C3 2014 Chevrolet Silverado 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 has an internal mode switch S signal circuit has an invalid voltage range of 0.70 – 0.96 V, for 2.7 s.

OBDII Code P18C3 2014 Chevrolet Silverado - Internal Mode Switch 'S' Circuit Stuck On Invalid Voltage Range - AutoCodes.com — P18C3 2014 Chevrolet Silverado Code - Internal Mode Switch 'S' Circuit Stuck On Invalid Voltage Range

What does this mean?

What are the Possible Causes of the DTC P18C3 2014 Chevrolet Silverado?

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 P18C3 2014 Chevrolet Silverado?

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 P18C3 2014 Chevrolet Silverado 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 P18C3 2014 Chevrolet Silverado code?

Need more information on how to fix the P18C3 2014 Chevrolet Silverado code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P18C3 2014 Chevrolet Silverado 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 P18C3 2014 Chevrolet Silverado Code

1. What are the common symptoms of OBDII code P18C3 in a 2014 Chevrolet Silverado?

The common symptoms of OBDII code P18C3 in a 2014 Chevrolet Silverado include issues with shifting gears, the transmission not engaging properly, and the vehicle going into limp mode.

2. What does the Internal Mode Switch 'S' Circuit Stuck On Invalid Voltage Range mean for a 2014 Chevrolet Silverado?

The code P18C3 indicates that there is an issue with the internal mode switch circuit in the transmission of the 2014 Chevrolet Silverado, specifically related to an invalid voltage range being detected.

3. What are some possible causes of the Internal Mode Switch 'S' Circuit Stuck On Invalid Voltage Range code in a 2014 Chevrolet Silverado?

Possible causes of OBDII code P18C3 in a 2014 Chevrolet Silverado include a faulty internal mode switch, wiring issues, a malfunctioning transmission control module, or a poor electrical connection.

4. How serious is OBDII code P18C3 in a 2014 Chevrolet Silverado?

OBDII code P18C3 in a 2014 Chevrolet Silverado should be addressed promptly as it can lead to transmission shifting issues, potential safety concerns, and reduced vehicle drivability.

5. Can I continue driving my 2014 Chevrolet Silverado with the Internal Mode Switch 'S' Circuit Stuck On Invalid Voltage Range code?

It is not recommended to continue driving a 2014 Chevrolet Silverado with the OBDII code P18C3 present, as it may lead to further transmission problems and potential damage if left unresolved.

6. How can I diagnose OBDII code P18C3 in my 2014 Chevrolet Silverado?

Diagnosing OBDII code P18C3 in a 2014 Chevrolet Silverado typically involves using a diagnostic scanner to retrieve the fault code, inspecting the internal mode switch and related wiring, and testing the transmission control module.

7. What are some possible repair options for fixing the Internal Mode Switch 'S' Circuit Stuck On Invalid Voltage Range code in a 2014 Chevrolet Silverado?

Repair options for addressing OBDII code P18C3 in a 2014 Chevrolet Silverado may include replacing the internal mode switch, repairing any damaged wiring, resetting the transmission control module, or seeking professional assistance for further diagnosis and repair.

8. How much does it cost to fix OBDII code P18C3 in a 2014 Chevrolet Silverado?

The cost of fixing OBDII code P18C3 in a 2014 Chevrolet Silverado can vary depending on the specific cause of the issue, parts needed for repair, labor costs, and whether you choose to address the problem yourself or take it to a professional mechanic.

9. Can I reset the OBDII code P18C3 in my 2014 Chevrolet Silverado without fixing the underlying issue?

While you can reset the OBDII code P18C3 in a 2014 Chevrolet Silverado using a diagnostic scanner, it is not recommended to do so without addressing the underlying issue, as the problem may persist and potentially worsen over time.

10. Are there any preventive measures to avoid OBDII code P18C3 in a 2014 Chevrolet Silverado?

To help prevent OBDII code P18C3 in a 2014 Chevrolet Silverado, it is advisable to perform regular maintenance checks on the transmission system, address any warning signs promptly, and ensure proper care and handling of the vehicle to avoid electrical issues that may trigger the code.