AutoCodes – GMC – P182A 2018 GMC Sierra

P182A 2018 GMC Sierra Code - Internal Mode Switch 'A' Circuit Low Voltage

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: P182A 2018 GMC Sierra indicates Internal Mode Switch 'A' Circuit Low Voltage.
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 542

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 P182A 2018 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 A signal circuit voltage is less than 0.7 V, for 1.75 s.

OBDII Code P182A 2018 GMC Sierra - Internal Mode Switch 'A' Circuit Low Voltage - AutoCodes.com — P182A 2018 GMC Sierra Code - Internal Mode Switch 'A' Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P182A 2018 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 P182A 2018 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 P182A 2018 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 P182A 2018 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 P182A 2018 GMC Sierra Code

1. What are the common symptoms of OBDII code P182A in a 2018 GMC Sierra?

- Common symptoms include issues with shifting gears, difficulty engaging reverse, and potentially triggering the vehicle to go into limp mode.

2. What does the Internal Mode Switch 'A' Circuit Low Voltage mean for a 2018 GMC Sierra?

- This code indicates that there is a low voltage condition in the circuit related to the internal mode switch 'A', which can impact the transmission's operation.

3. What are the possible causes of the Internal Mode Switch 'A' Circuit Low Voltage code in a 2018 GMC Sierra?

- Potential causes include a faulty internal mode switch, damaged wiring or connectors in the circuit, low battery voltage, or issues with the transmission control module.

4. How can I diagnose OBDII code P182A in my 2018 GMC Sierra?

- Diagnosis typically involves using a scan tool to read the code, checking the internal mode switch and related wiring for damage, and testing the voltage in the circuit.

5. Can I continue driving my 2018 GMC Sierra with the Internal Mode Switch 'A' Circuit Low Voltage code?

- It is not recommended to drive the vehicle with this code present, as it can lead to transmission issues and further damage if not addressed promptly.

6. How can I repair OBDII code P182A in my 2018 GMC Sierra?

- Repairs may involve replacing the internal mode switch, repairing damaged wiring or connectors, addressing low battery voltage issues, or reprogramming the transmission control module.

7. Is it necessary to reset the OBDII code P182A after repairs in a 2018 GMC Sierra?

- Yes, it is important to clear the code after completing repairs to see if the issue has been resolved and to prevent potential confusion in future diagnostics.

8. Are there any DIY tips for addressing the Internal Mode Switch 'A' Circuit Low Voltage code in a 2018 GMC Sierra?

- While some basic checks like inspecting wiring and connectors can be done DIY, complex repairs or component replacements may require professional help.

9. Can weather conditions affect the occurrence of OBDII code P182A in a 2018 GMC Sierra?

- Extreme weather conditions, especially those impacting electrical components, can potentially contribute to issues leading to the Internal Mode Switch 'A' Circuit Low Voltage code.

10. How long does it typically take to repair OBDII code P182A in a 2018 GMC Sierra?

- The repair time can vary based on the exact cause of the issue and the complexity of the repair needed, but it may take a few hours to a day to complete the necessary fixes.