AutoCodes – Generic – P1812

P1812 Code - Transmission Fluid Overtemperature

Quick Answer

The Powertrain Control Module (PCM) detects a Transmission Fluid Temperature (TFT) Sensor input of more than 266°F, all conditions met for over 6 minutes, 48 seconds. Common causes include Faulty Transmission Fluid Temperature (TFT) Sensor, Transmission Fluid Temperature (TFT) Sensor harness is open or shorted, Transmission Fluid Temperature (TFT) Sensor circuit poor electrical connection. 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: P1812 indicates Transmission Fluid Overtemperature.
Common causes: Common causes include Faulty Transmission Fluid Temperature (TFT) Sensor, Transmission Fluid Temperature (TFT) Sensor harness is open or shorted, Transmission Fluid Temperature (TFT) Sensor circuit poor electrical connection.
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 17,477

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 Sep 20, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
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Code P1812 Description

The Powertrain Control Module (PCM) detects a Transmission Fluid Temperature (TFT) Sensor input of more than 266°F, all conditions met for over 6 minutes, 48 seconds.

OBDII Code P1812 - Transmission Fluid Overtemperature - AutoCodes.com — P1812 Code - Transmission Fluid Overtemperature

What does this mean?

What are the Possible Causes of the DTC P1812?

Faulty Transmission Fluid Temperature (TFT) Sensor
Transmission Fluid Temperature (TFT) Sensor harness is open or shorted
Transmission Fluid Temperature (TFT) Sensor circuit poor electrical connection

How to Fix the DTC P1812?

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 P1812 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 P1812 code?

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Need Help with the Code?

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Information for Specific Makes

P1812 Buick — Transmission Fluid Overtemperature
P1812 Cadillac — Transmission Fluid Overtemperature
P1812 Chevrolet — Transmission Fluid Overtemperature
P1812 Ford — 4-Wheel Drive Mode Select Circuit Failure
P1812 GMC — Transmission Fluid Overtemperature

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.