Engine-Codes.com
Engine-Codes – Chevrolet – P1838 2018 Chevrolet Silverado

P1838 2018 Chevrolet Silverado Code - Internal Mode Switch 'A' Circuit High Voltage

Quick Answer

The P1838 diagnostic trouble code (DTC) for a 2018 Chevrolet Silverado indicates an issue with the Internal Mode Switch 'A' Circuit High Voltage. Common causes include Faulty Internal Mode Switch, Wiring or connection issues in the IMS circuit, Corrosion or damage to IMS components. 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
P1838 2018 Chevrolet Silverado indicates Internal Mode Switch 'A' Circuit High Voltage.
Common causes
Common causes include Faulty Internal Mode Switch, Wiring or connection issues in the IMS circuit, Corrosion or damage to IMS components.
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.
What is this?
Table of contents Created and updated by William Orellana on Sep 17, 2024
💬 Need more help? Ask Auto Expert for instant answers — it's free!
AutoCodes App

Fix Your Car Smarter

Try the New AutoCodes App!

Get complete OBDII diagnostics, repair solutions, and cost estimates, plus AI chat support on demand.

AutoCodes App on Google Play

Code P1838 2018 Chevrolet Silverado Description

The P1838 diagnostic trouble code (DTC) for a 2018 Chevrolet Silverado indicates an issue with the Internal Mode Switch 'A' Circuit High Voltage. The Internal Mode Switch (IMS) is a component of the transmission system that communicates the gear selection to the vehicle's engine control module (ECM). When the ECM detects a high voltage in the circuit related to the IMS 'A', it triggers the P1838 code.

OBDII Code P1838 2018 Chevrolet Silverado - Internal Mode Switch 'A' Circuit High Voltage
P1838 2018 Chevrolet Silverado Code - Internal Mode Switch 'A' Circuit High Voltage

Common Causes of P1838 2018 Chevrolet Silverado

  1. Faulty Internal Mode Switch
  2. Wiring or connection issues in the IMS circuit
  3. Corrosion or damage to IMS components
  4. ECM malfunction or software glitch
  5. Electrical issues such as a short circuit or voltage spike

Symptoms of P1838 2018 Chevrolet Silverado

  1. Erratic shifting or failure to shift gears
  2. Delayed engagement when shifting gears
  3. Harsh or rough shifting
  4. Illumination of the Check Engine Light
  5. Reduced fuel efficiency

How to Fix P1838 2018 Chevrolet Silverado

  1. Diagnose the issue using a scan tool to confirm the P1838 code and pinpoint the exact cause.
  2. Inspect the Internal Mode Switch and its circuit for any visible damage, corrosion, or loose connections.
  3. Test the voltage in the IMS circuit to determine if it is within the specified range.
  4. Replace the Internal Mode Switch if it is found to be faulty, ensuring proper installation and connection.
  5. Clear the DTC and test drive the vehicle to confirm that the issue has been resolved.

Cost to Fix P1838 2018 Chevrolet Silverado

The cost of repairing the Internal Mode Switch 'A' Circuit High Voltage issue can vary depending on the specific cause of the problem and the labor rates in your area. In general, the cost of parts for replacing the IMS can range from $100 to $300, while the labor cost can be between $100 and $200. Overall, the total repair cost for addressing the P1838 code may range from $200 to $500. Keep in mind that these are rough estimates, and actual costs may differ based on various factors. It is recommended to consult with a qualified mechanic or repair shop to get a more accurate cost estimate for your specific situation.

Need more information about the P1838 2018 Chevrolet Silverado code?

Need more information on how to fix the P1838 2018 Chevrolet Silverado code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1838 2018 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 P1838 2018 Chevrolet Silverado Code

1. What are the common symptoms of OBDII code P1838 in a 2018 Chevrolet Silverado?

- Common symptoms include issues with shifting gears, hesitation or jerking during acceleration, and the Check Engine Light illuminating on the dashboard.

2. What does the OBDII code P1838 'Internal Mode Switch A Circuit High Voltage' indicate in a 2018 Chevrolet Silverado?

- This code indicates that the internal mode switch circuit A is detecting a high voltage condition, which can impact the transmission's operation.

3. What are the possible causes of OBDII code P1838 in a 2018 Chevrolet Silverado?

- Possible causes include a faulty internal mode switch, damaged wiring or connectors in the circuit, low transmission fluid levels, or issues with the transmission control module.

4. How can I diagnose the OBDII code P1838 in my 2018 Chevrolet Silverado?

- Diagnosing this code typically involves using a scan tool to retrieve the fault codes, checking the internal mode switch for proper operation, inspecting the wiring and connectors for damage, and testing the transmission fluid level.

5. Can I continue driving my 2018 Chevrolet Silverado with OBDII code P1838?

- It is not recommended to continue driving the vehicle with this code present, as it can lead to transmission issues and potentially cause further damage. It is advisable to address the problem promptly.

6. How can I repair OBDII code P1838 in my 2018 Chevrolet Silverado?

- Repair options may include replacing the internal mode switch, repairing or replacing damaged wiring or connectors, ensuring the transmission fluid levels are adequate, and addressing any issues with the transmission control module.

7. Will resetting the Check Engine Light resolve OBDII code P1838 in my 2018 Chevrolet Silverado?

- Simply resetting the Check Engine Light will not fix the underlying issue causing the code. It is important to diagnose and repair the root cause of the problem to prevent it from recurring.

8. Is OBDII code P1838 a common issue in 2018 Chevrolet Silverado vehicles?

- While it may not be extremely common, some 2018 Chevrolet Silverado owners have reported experiencing this code related to internal mode switch circuit issues.

9. Can a DIY enthusiast fix OBDII code P1838 in a 2018 Chevrolet Silverado?

- Depending on the individual's skill level and access to tools, a DIY enthusiast may be able to address this code by following repair procedures outlined in the vehicle's service manual or seeking assistance from automotive forums.

10. How much should I expect to pay for repairing OBDII code P1838 in my 2018 Chevrolet Silverado?

- The cost of repairs can vary depending on the exact cause of the issue and whether you choose to address it yourself or take it to a professional mechanic. It is advisable to obtain quotes from local repair shops for an accurate estimate.

Discuss the causes and fixes for P1838 2018 Chevrolet Silverado OBDII Code

Submit a New Comment

Code P1838 2018 Chevrolet Silverado comments

No comments found for this page.