AutoCodes – Chevrolet – P18B7 2014 Chevrolet Silverado

P18B7 2014 Chevrolet Silverado Code - Internal Mode Switch 'C' Circuit Shorted

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: P18B7 2014 Chevrolet Silverado indicates Internal Mode Switch 'C' Circuit Shorted.
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 269

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 P18B7 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 the internal mode switch C signal circuit voltage is between 0.966–1.68 V, for 1.75 s.

OBDII Code P18B7 2014 Chevrolet Silverado - Internal Mode Switch 'C' Circuit Shorted - AutoCodes.com — P18B7 2014 Chevrolet Silverado Code - Internal Mode Switch 'C' Circuit Shorted

What does this mean?

What are the Possible Causes of the DTC P18B7 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 P18B7 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 P18B7 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 P18B7 2014 Chevrolet Silverado code?

Need more information on how to fix the P18B7 2014 Chevrolet Silverado 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 P18B7 2014 Chevrolet Silverado Code

1. What does the OBDII code P18B7 mean for a 2014 Chevrolet Silverado?

The P18B7 code indicates an issue with the Internal Mode Switch 'C' Circuit, specifically a shorted condition.

2. What are the common symptoms of code P18B7 in a 2014 Chevrolet Silverado?

Symptoms may include difficulty shifting gears, the transmission stuck in one gear, illumination of the check engine light, or erratic transmission behavior.

3. What causes the P18B7 code to appear?

The code is typically caused by a short circuit in the wiring or connectors of the Internal Mode Switch 'C,' a faulty internal mode switch, or transmission control module (TCM) issues.

4. Can driving with the P18B7 code damage my 2014 Chevrolet Silverado?

Yes, continuing to drive with this code can lead to further transmission problems and potentially damage the transmission system.

5. How do I diagnose the P18B7 code on my Silverado?

Start by visually inspecting the wiring and connectors for damage or corrosion. Use a multimeter to test the switch circuit for shorts and verify the function of the internal mode switch.

6. What repairs are needed to fix the P18B7 code?

Repairs may include replacing damaged wiring or connectors, replacing the internal mode switch, or reprogramming or replacing the transmission control module.

7. How much does it cost to repair the P18B7 code on a 2014 Chevrolet Silverado?

The cost varies depending on the root cause, ranging from $100 for wiring repairs to $500 or more for replacing the internal mode switch or TCM.

8. Is the Internal Mode Switch the same as the Transmission Range Sensor?

Yes, in many cases, the internal mode switch is part of the transmission range sensor assembly, which detects gear position.

9. Can a low battery cause the P18B7 code to appear?

While uncommon, a low or unstable battery voltage can sometimes cause electrical faults, including this code. Ensure the battery and charging system are functioning properly.

10. Do I need professional help to fix the P18B7 code?

If youâ€™re not experienced with diagnosing electrical or transmission issues, itâ€™s best to seek assistance from a qualified mechanic to avoid further damage.