AutoCodes – Generic – P0843

P0843 Code - Transmission Fluid Pressure Sensor/Switch 'A' Circuit High

Quick Answer

The Torque Converter Clutch (TCC) release switch is part of the automatic Transmission Fluid Pressure (TFP) manual valve position switch. Common causes include Low transmission fluid level, Dirty transmission fluid, Faulty Transmission Fluid Pressure Sensor/Switch 'A'. 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: P0843 indicates Transmission Fluid Pressure Sensor/Switch 'A' Circuit High.
Common causes: Common causes include Low transmission fluid level, Dirty transmission fluid, Faulty Transmission Fluid Pressure Sensor/Switch 'A'.
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 59,500

How popular is this code, among other codes? Medium

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 Aug 03, 2022

Description
Possible Causes
How To Fix
Tech Notes ▶
Cost to Diagnose
Comments
Add Comment

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

Code P0843 Description

The Torque Converter Clutch (TCC) release switch is part of the automatic Transmission Fluid Pressure (TFP) manual valve position switch. The TFP manual valve position switch is mounted to the transmission valve body. The TCC release switch is a normally-closed switch.
When the TCC is released, TCC release fluid pressure opens the TCC release switch which opens the TCC release pressure circuit. When the voltage on the circuit is high (switch open), the Powertrain Control Module (PCM) recognizes that the TCC is no longer engaged.

OBDII Code P0843 - Transmission Fluid Pressure Sensor/Switch 'A' Circuit High - AutoCodes.com — P0843 Code - Transmission Fluid Pressure Sensor/Switch 'A' Circuit High

What does this mean?

What are the Possible Causes of the DTC P0843?

Low transmission fluid level
Dirty transmission fluid
Faulty Transmission Fluid Pressure Sensor/Switch 'A'
Transmission Fluid Pressure Sensor/Switch 'A' harness or connectors
Transmission Fluid Pressure Sensor/Switch 'A' circuit is open or shorted
Transmission internal mechanical problem

How to Fix the DTC P0843?

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 does this mean?

Code Tech Notes

User Submitted Video

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0843 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 P0843 code?

Need more information on how to fix the P0843 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0843 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P0843 Acura — Transmission Fluid Pressure Switch 'A' 2nd Clutch Circuit High
P0843 Buick — Transmission Fluid Pressure Switch 1 Circuit High Voltage
P0843 Cadillac — Transmission Fluid Pressure Switch 1 Circuit High Voltage
P0843 Chevrolet — Transmission Fluid Pressure Switch 1 Circuit High Voltage
P0843 Dodge — Transmission Fluid Pressure Sensor/Switch 'A' Circuit High
P0843 GMC — Transmission Fluid Pressure Switch 1 Circuit High Voltage
P0843 Honda — Transmission Fluid Pressure Switch 'A' 2nd Clutch Circuit High
P0843 Mercedes-Benz — Transmission Fluid Pressure Sensor/Switch 'A' Circuit High

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.