AutoCodes – GMC – P0873 GMC

P0873 GMC Code - Transmission Fluid Pressure Switch 3 Circuit High Voltage

Quick Answer

The transmission fluid pressure switch, also known as the pressure switch manifold, is a multiple switch assembly made up of 3 normally open pressure switches and 1 normally closed pressure switch. 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: P0873 GMC indicates Transmission Fluid Pressure Switch 3 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 1,095

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 P0873 GMC Description

The transmission fluid pressure switch, also known as the pressure switch manifold, is a multiple switch assembly made up of 3 normally open pressure switches and 1 normally closed pressure switch. Pressure switch 1 monitors shift valve 1 positioning, pressure switch 2 monitors shift valve 2 positioning, pressure switch 3 monitors shift valve 3 positioning, and pressure switch 4 monitors the position of the manual selector valve. The TCM provides a signal circuit to each of the pressure switches. The TCM constantly monitors the circuits to determine the position of the shift valves. The position of shift valves 1, 2, and 3 is controlled by 3 normally closed shift solenoids. When energized, shift solenoid 1 directs fluid pressure to shift valve 1, shift solenoid 2 directs fluid pressure to shift valve 2, and shift solenoid 3 directs fluid pressure to shift valve 3, which strokes the shift valves. When a shift valve is stroked, an exhaust passage is blocked and fluid pressure increases, closing the normally open pressure switch. The Diagnostic Trouble Code (DTC) will be set when the TCM detects that transmission fluid pressure switch 3 signal circuit is High when shift solenoid 3 is commanded ON for 1 s.

OBDII Code P0873 GMC - Transmission Fluid Pressure Switch 3 Circuit High Voltage - AutoCodes.com — P0873 GMC Code - Transmission Fluid Pressure Switch 3 Circuit High Voltage

What does this mean?

What are the Possible Causes of the DTC P0873 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
Faulty Transmission Control Module (TCM)

How to Fix the DTC P0873 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 P0873 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.

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Need Help with the Code?

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Information for Specific GMC Models

P0873 2014 GMC Sierra — Transmission Fluid Pressure Switch 3 Circuit High Voltage
P0873 2015 GMC Sierra — Transmission Fluid Pressure Switch 3 Circuit High Voltage
P0873 2016 GMC Sierra — Transmission Fluid Pressure Switch 3 Circuit High Voltage
P0873 2017 GMC Sierra — Transmission Fluid Pressure Switch 3 Circuit High Voltage
P0873 2018 GMC Sierra — Transmission Fluid Pressure Switch 3 Circuit High 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 P0873 GMC Code

1. What are the common symptoms of OBDII code P0873 in a GMC vehicle?

The common symptoms of OBDII code P0873 in a GMC vehicle include harsh shifting, transmission slippage, transmission overheating, and possibly an illuminated Check Engine Light.

2. What can cause the OBDII code P0873 related to Transmission Fluid Pressure Switch 3 Circuit High Voltage in a GMC vehicle?

The OBDII code P0873 related to Transmission Fluid Pressure Switch 3 Circuit High Voltage in a GMC vehicle can be caused by issues such as a faulty transmission fluid pressure switch, a short or open circuit in the wiring, or a malfunctioning transmission control module.

3. How can I diagnose the OBDII code P0873 in my GMC vehicle?

Diagnosing the OBDII code P0873 in a GMC vehicle involves using a diagnostic scanner to read the code, checking the transmission fluid level and condition, inspecting the wiring and connectors related to the pressure switch, and testing the pressure switch itself for proper function.

4. What are the possible repair options for OBDII code P0873 in a GMC vehicle?

Possible repair options for OBDII code P0873 in a GMC vehicle include replacing the faulty transmission fluid pressure switch, repairing any damaged wiring or connectors, resetting the trouble code with a scanner after making necessary repairs, and ensuring proper transmission fluid levels and quality.

5. Can driving with OBDII code P0873 in a GMC vehicle cause further damage?

Driving with OBDII code P0873 in a GMC vehicle can potentially cause further damage to the transmission system if left unresolved. It is recommended to address the issue promptly to prevent any serious transmission problems.

6. How much does it typically cost to repair OBDII code P0873 in a GMC vehicle?

The cost of repairing OBDII code P0873 in a GMC vehicle can vary depending on the exact cause of the issue, the cost of parts needed for repair, and labor charges. It is advisable to consult a professional mechanic for an accurate estimate.

7. Is it safe to continue driving my GMC vehicle with OBDII code P0873 present?

It is not recommended to continue driving your GMC vehicle with OBDII code P0873 present, as it can lead to potential transmission issues and further damage. It is best to address the problem as soon as possible.

8. Can a DIY enthusiast fix OBDII code P0873 in a GMC vehicle?

While some DIY enthusiasts may have the skills and tools to diagnose and repair OBDII code P0873 in a GMC vehicle, it is a complex issue related to the transmission system. It is recommended to seek professional help for accurate diagnosis and proper repair.

9. How long does it take to repair OBDII code P0873 in a GMC vehicle?

The time required to repair OBDII code P0873 in a GMC vehicle can vary depending on the extent of the issue, availability of parts, and the expertise of the mechanic. It is best to consult with a professional for an estimated repair time.

10. Are there any preventive measures to avoid OBDII code P0873 in a GMC vehicle?

To prevent OBDII code P0873 in a GMC vehicle, it is essential to maintain regular transmission fluid checks and changes, address any transmission issues promptly, and follow the manufacturer's recommended maintenance schedule for your vehicle.