AutoCodes – GMC – P0877 GMC

P0877 GMC Code - Transmission Fluid Pressure Switch 4 Circuit Low Voltage

Quick Answer

The Transmission Fluid Pressure (TFP) switch 4 is part of the Transmission 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: P0877 GMC indicates Transmission Fluid Pressure Switch 4 Circuit Low 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 3,279

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 03, 2022

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P0877 GMC Description

The Transmission Fluid Pressure (TFP) switch 4 is part of the Transmission Control Solenoid Valve Assembly which has no serviceable parts. The Transmission Control Module (TCM) supplies a signal circuit to the TFP switch 4. The TFP switch 4 has an internal case ground. TFP switch 4 is normally closed or LOW. When oil pressure is present at the TFP switch 4, the switch is open or HIGH. The normal LOW pressure control solenoid 5 controls pressure to the 1-2-3-4 clutch regulator valve. The TCM monitors the TFP switch 4 to determine the position of the 1-2-3-4 clutch regulator valve. When the 1-2-3-4 clutch is commanded OFF, pressure is present on the TFP switch 4. When the 1-2-3-4 clutch is commanded ON, the 1-2-3-4 clutch regulator valve moves and pressure to the TFP switch 4 is exhausted through the 1-2-3-4 clutch regulator valve. The Diagnostic Trouble Code (DTC) will be set when the TCM detects that the TFP switch 4 signal voltage remains LOW after the 1-2-3-4 clutch transitions from a HIGH pressure state to a LOW pressure state. The TCM counts each incident. The DTC sets when 5 counts are accumulated.

OBDII Code P0877 GMC - Transmission Fluid Pressure Switch 4 Circuit Low Voltage - AutoCodes.com — P0877 GMC Code - Transmission Fluid Pressure Switch 4 Circuit Low Voltage

What does this mean?

What are the Possible Causes of the DTC P0877 GMC?

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 P0877 GMC?

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 P0877 GMC 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 P0877 GMC code?

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Need Help with the Code?

Get the P0877 GMC code diagnosed by a professional: Find a repair shop in your area

Information for Specific GMC Models

P0877 2014 GMC Sierra — Transmission Fluid Pressure Switch 4 Circuit Low Voltage
P0877 2015 GMC Sierra — Transmission Fluid Pressure Switch 4 Circuit Low Voltage
P0877 2016 GMC Sierra — Transmission Fluid Pressure Switch 4 Circuit Low Voltage
P0877 2017 GMC Sierra — Transmission Fluid Pressure Switch 4 Circuit Low Voltage
P0877 2018 GMC Sierra — Transmission Fluid Pressure Switch 4 Circuit Low Voltage

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 P0877 GMC Code

1. What are common symptoms of OBDII code P0877 in a GMC vehicle?

- Common symptoms include harsh shifting, transmission slippage, decreased fuel efficiency, and an illuminated Check Engine Light.

2. What can cause the Transmission Fluid Pressure Switch 4 Circuit Low Voltage code in a GMC vehicle?

- Possible causes include a faulty transmission fluid pressure switch, damaged wiring or connectors, low transmission fluid levels, or a malfunctioning transmission control module.

3. How serious is OBDII code P0877 in a GMC vehicle?

- This code can lead to transmission issues and potentially cause further damage if left unresolved. It is recommended to address the issue promptly to prevent more significant problems.

4. How can I diagnose the cause of OBDII code P0877 in my GMC vehicle?

- Diagnosis typically involves checking the transmission fluid level and condition, inspecting the wiring and connectors related to the pressure switch, and using a diagnostic scanner to pinpoint the exact issue.

5. Can I drive my GMC vehicle with the P0877 code present?

- It is not recommended to drive the vehicle with this code active, as it can affect the transmission's performance and lead to further damage. It is best to address the issue before driving the vehicle again.

6. Is it possible to reset the P0877 code in a GMC vehicle?

- While you can clear the code using a diagnostic scanner, it is crucial to address the root cause of the issue to prevent the code from reappearing. Simply clearing the code without fixing the underlying problem may not solve the issue.

7. How can I repair OBDII code P0877 in my GMC vehicle?

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

8. Will OBDII code P0877 cause my GMC vehicle to go into "limp mode"?

- In some cases, this code can trigger the vehicle's limp mode to protect the transmission from further damage. If you experience reduced power or functionality, it may be due to the vehicle entering limp mode.

9. Can a DIY enthusiast fix OBDII code P0877 in a GMC vehicle?

- Depending on your skill level and access to tools, some DIY enthusiasts may be able to address this code by following repair guides and using the necessary equipment. However, complex transmission issues may require professional assistance.

10. How much does it typically cost to repair OBDII code P0877 in a GMC vehicle?

- The cost of repairing this code can vary based on the specific issue causing it, the labor rates in your area, and whether you choose to address the problem yourself or seek professional help. Costs may range from a few hundred to over a thousand dollars.