P0843Transmission

Transmission Fluid Pressure Sensor A Circuit High

P0843 means the transmission fluid pressure sensor or switch A circuit is reading high, often an open circuit, a short to power, or a failed sensor. The controller loses accurate pressure feedback.

🚗 Limited. A bad pressure sensor signal can cause erratic shifting or limp mode.

MEDIUM

severity

🎯 Top Causes, Ranked by Likelihood

#1Faulty transmission pressure sensor A$100-$350

35%

A failed sensor outputs high voltage.

#2Open or high-resistance wiring$100-$300

30%

An open signal or ground wire raises the reading.

#3Short to power in wiring$100-$300

20%

A wire touching voltage pulls the circuit high.

#4Poor connector or corrosion$20-$100

15%

A corroded connector produces a high reading.

🩺 Common Symptoms

Erratic or harsh shifting
Limp mode
Check engine light
Delayed engagement
Poor shift quality

💰 Repair Cost: DIY vs Shop

DIY Cost

$20-$350

Shop Cost

$100-$450

📋 Free OBD2 Code Cheat Sheet

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

🔧 How to Diagnose P0843

1Check fluid level and condition first

2Inspect the pressure sensor connector and wiring

3Check the ground circuit for an open

4Replace the transmission pressure sensor if faulty

❓ Frequently Asked Questions

Can I drive with P0843?

Only briefly. Loss of pressure feedback can cause erratic shifting or limp mode. Diagnose it soon.

What does P0843 mean?

The transmission fluid pressure sensor A circuit reads high, usually an open circuit, a short to power, or a bad sensor.

How much to fix P0843?

A replacement sensor is $100-$350, and wiring repairs run $100-$300.

🔗 Related Codes

P0842P0847P0872P0873P0731