AutoCodes – Buick – P183A Buick

P183A Buick Code - Internal Mode Switch 2 D1 Circuit Low Voltage

Quick Answer

The automatic transmission manual shift shaft position switch assembly, also called the internal mode switch assembly, contains two sliding hall-effect switch assemblies attached to the control valve body within the transmission. Common causes include Faulty Manual Shift Shaft Position Switch Assembly, Manual Shift Shaft Position Switch Assembly harness is open or shorted, Manual Shift Shaft Position Switch Assembly 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: P183A Buick indicates Internal Mode Switch 2 D1 Circuit Low Voltage.
Common causes: Common causes include Faulty Manual Shift Shaft Position Switch Assembly, Manual Shift Shaft Position Switch Assembly harness is open or shorted, Manual Shift Shaft Position Switch Assembly 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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 919

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 Jan 30, 2020

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P183A Buick Description

The automatic transmission manual shift shaft position switch assembly, also called the internal mode switch assembly, contains two sliding hall-effect switch assemblies attached to the control valve body within the transmission. The 9 outputs from the switches indicate which position is selected by the transmission manual shaft. Four outputs (A, B, C, P) are range selection inputs to the transmission control module (TCM). Five outputs (R1, R2, D1, D2, S) are direction selection inputs to the hybrid powertrain control module. The Range input signals are represented as TCM scan tool parameters, Internal Mode Switch A, B, C, and P. The Direction input signals are represented as hybrid powertrain control module scan tool parameters, Internal Mode Switch 2 - R1, R2, D1, D2, and S. The input voltage at the modules is high when a switch is open and low when a switch is closed to earth. Each control module independently supplies power and earth to its respective switch assembly.
The hybrid powertrain control module is internal to the power inverter module, often referred to as the drive motor generator power inverter module and is not serviced separately.

OBDII Code P183A Buick - Internal Mode Switch 2 D1 Circuit Low Voltage - AutoCodes.com — P183A Buick Code - Internal Mode Switch 2 D1 Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P183A Buick?

Faulty Manual Shift Shaft Position Switch Assembly
Manual Shift Shaft Position Switch Assembly harness is open or shorted
Manual Shift Shaft Position Switch Assembly circuit poor electrical connection

How to Fix the DTC P183A Buick?

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 P183A Buick 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 P183A Buick code?

Need more information on how to fix the P183A Buick code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P183A Buick 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 P183A Buick Code

What does the OBDII code P183A mean for a Buick?

Code P183A indicates an issue with the Internal Mode Switch 2 D1 Circuit, specifically low voltage detected by the transmission control module (TCM).

What are the common symptoms of code P183A on a Buick?

Symptoms may include erratic shifting, transmission stuck in a single gear, reduced performance, or the illumination of the check engine light.

What causes the P183A code to appear on a Buick?

The code can be caused by issues such as a faulty internal mode switch, damaged wiring or connectors in the circuit, or a malfunctioning transmission control module.

How can I diagnose the P183A code?

Diagnosis typically involves using a scan tool to verify the code, inspecting the wiring and connectors for damage, and testing the internal mode switch for proper operation.

Can I still drive my Buick with the P183A code active?

Driving with this code may result in transmission performance issues. It's recommended to address the problem promptly to avoid further damage.

How much does it typically cost to repair a P183A code on a Buick?

Repair costs can vary but may range from $150 to $600, depending on whether the issue is related to wiring repairs, switch replacement, or TCM diagnosis.

What tools are needed to troubleshoot the P183A code?

Tools may include a scan tool or OBDII reader, a multimeter for testing voltage, and basic hand tools to inspect and repair wiring or components.

Does clearing the P183A code solve the problem?

Clearing the code without fixing the underlying issue will not resolve the problem, and the code is likely to return.

Can a faulty internal mode switch cause the P183A code?

Yes, a malfunctioning internal mode switch is a common cause of this code and may need replacement.

How can I prevent the P183A code from recurring on my Buick?

Regular maintenance, including inspecting wiring and connectors for damage and ensuring proper transmission fluid levels, can help prevent this code from appearing.