AutoCodes – GMC – P0843 2016 GMC Sierra

P0843 2016 GMC Sierra Code - Transmission Fluid Pressure Switch 1 Circuit High Voltage

Quick Answer

The Transmission Fluid Pressure (TFP) switch 1 is part of the control solenoid valve assembly, which has no serviceable parts. Common causes include Low transmission fluid level, Dirty transmission fluid, Faulty Transmission Control Solenoid Valve Assembly. 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 2016 GMC Sierra indicates Transmission Fluid Pressure Switch 1 Circuit High Voltage.
Common causes: Common causes include Low transmission fluid level, Dirty transmission fluid, Faulty Transmission Control Solenoid Valve Assembly.
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 292

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 Aug 02, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P0843 2016 GMC Sierra Description

The Transmission Fluid Pressure (TFP) switch 1 is part of the control solenoid valve assembly, which has no serviceable parts. The Transmission Control Module (TCM) supplies a signal circuit to the TFP Switch 1. The TFP Switch 1 has an internal case ground. TFP Switch 1 is normally closed or LOW. When oil pressure is present at the TFP Switch 1, the switch is open or HIGH. The normally high clutch pressure control (PC) solenoid 2 controls pressure to the 3-5 reverse clutch regulator valve. The TCM monitors the TFP switch 1 to determine the position of the 3-5 reverse clutch regulator valve. When the 3-5 reverse clutch is commanded OFF, pressure is present on the TFP switch 1. When the 3-5 reverse clutch is commanded ON, the 3-5 reverse clutch regulator valve moves and pressure to the TFP switch 1 is exhausted through the 3-5 reverse clutch regulator valve. The Diagnostic Trouble Code (DTC) will be set when the TCM detects that the TFP switch 1 signal voltage remains HIGH after the 3-5-R clutch transitions from a LOW pressure state to a HIGH pressure state. The TCM counts each incident. The DTC sets when 35 counts are accumulated.

OBDII Code P0843 2016 GMC Sierra - Transmission Fluid Pressure Switch 1 Circuit High Voltage - AutoCodes.com — P0843 2016 GMC Sierra Code - Transmission Fluid Pressure Switch 1 Circuit High Voltage

What does this mean?

What are the Possible Causes of the DTC P0843 2016 GMC Sierra?

Low transmission fluid level
Dirty transmission fluid
Faulty Transmission Control Solenoid Valve Assembly
Transmission Control Solenoid Valve Assembly harness is open or shorted
Transmission Control Solenoid Valve Assembly circuit poor electrical connection

How to Fix the DTC P0843 2016 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 P0843 2016 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 P0843 2016 GMC Sierra code?

Need more information on how to fix the P0843 2016 GMC Sierra code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0843 2016 GMC Sierra 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 P0843 2016 GMC Sierra Code

1. What are the common symptoms of OBDII code P0843 in a 2016 GMC Sierra?

The common symptoms of OBDII code P0843 in a 2016 GMC Sierra may include harsh shifting, transmission slipping, transmission overheating, and the transmission going into "limp mode."

2. What does OBDII code P0843 indicate in a 2016 GMC Sierra?

OBDII code P0843 in a 2016 GMC Sierra indicates a problem with the Transmission Fluid Pressure Switch 1 Circuit High Voltage.

3. What are the possible causes of OBDII code P0843 in a 2016 GMC Sierra?

Possible causes of OBDII code P0843 in a 2016 GMC Sierra include a faulty transmission fluid pressure switch, wiring or connector issues, low transmission fluid level, or a malfunctioning transmission control module.

4. How serious is OBDII code P0843 in a 2016 GMC Sierra?

OBDII code P0843 in a 2016 GMC Sierra should be addressed promptly to prevent potential transmission damage or unsafe driving conditions.

5. How can I diagnose OBDII code P0843 in a 2016 GMC Sierra?

Diagnosing OBDII code P0843 in a 2016 GMC Sierra typically involves using a scan tool to check for the code, inspecting the transmission fluid level and condition, and testing the transmission fluid pressure switch and related circuitry.

6. Can I drive my 2016 GMC Sierra with OBDII code P0843?

It is not recommended to drive a 2016 GMC Sierra with OBDII code P0843, as it can lead to further transmission issues and potentially unsafe driving conditions.

7. How can I repair OBDII code P0843 in a 2016 GMC Sierra?

Repairing OBDII code P0843 in a 2016 GMC Sierra may involve replacing the transmission fluid pressure switch, repairing or replacing damaged wiring or connectors, ensuring proper transmission fluid level, and resetting the fault code.

8. Is it possible to reset OBDII code P0843 in a 2016 GMC Sierra without repairs?

While you can clear the fault code temporarily, it is crucial to address the underlying issue causing OBDII code P0843 in a 2016 GMC Sierra to prevent further damage and ensure safe operation.

9. How much does it cost to fix OBDII code P0843 in a 2016 GMC Sierra?

The cost to fix OBDII code P0843 in a 2016 GMC Sierra can vary depending on the exact cause of the issue, parts needed for replacement, and labor costs at a repair shop. It's recommended to get a diagnosis and estimate from a professional technician.

10. Can weather conditions affect OBDII code P0843 in a 2016 GMC Sierra?

Extreme weather conditions can potentially affect the operation of the transmission fluid pressure switch and related components, leading to the triggering of OBDII code P0843 in a 2016 GMC Sierra.