P0871Transmission

Transmission Fluid Pressure Sensor/Switch C Circuit

P0871 means a circuit fault in transmission fluid pressure sensor or switch C. It is usually a sensor, wiring, or connector problem, but real pressure issues should be ruled out.

🚗 Often drivable, but pressure sensing faults can affect shift control. Have it checked soon.

MEDIUM

severity

🎯 Top Causes, Ranked by Likelihood

#1Faulty pressure sensor/switch C$50-$300

40%

The sensor fails electrically and sets the code.

#2Wiring or connector fault$40-$300

30%

Damaged wiring or a corroded connector.

#3Low or contaminated fluid$80-$300

20%

Poor fluid can affect readings and shifting.

#4Internal transmission fault$200-$1500

10%

Rarely, an internal problem affects the signal.

🩺 Common Symptoms

Harsh or erratic shifting
Check engine light
Wrong pressure reading
Possible limp mode

💰 Repair Cost: DIY vs Shop

DIY Cost

$50-$300

Shop Cost

$150-$500

📋 Free OBD2 Code Cheat Sheet

The 50 most common codes with likely cause and DIY fix cost. Sent once, no spam.

🔧 How to Diagnose P0871

1Check the fluid level and condition

2Inspect the sensor wiring and connector

3Test the pressure sensor

4Replace the sensor if faulty

❓ Frequently Asked Questions

Can I drive with P0871?

Often yes, but shift control can be affected. Have it checked soon.

How much to fix P0871?

A pressure sensor is often $150-$500 installed.

Is P0871 serious?

Medium severity. It affects pressure sensing used for shift control.

🔗 Related Codes

P0868P0872P0873P0745