AutoCodes – Generic – P1843

P1843 Code - 1-2 Shift Solenoid Circuit High Input Voltage

Quick Answer

With the engine runtime over 5 seconds, system voltage from 8-18v, Fuel Cutoff inactive, 1-2 Shift Solenoid commanded on by the Powertrain Control Module (PCM), the PCM detects a continuous short to power on the 1-2 Shift Solenoid feedback circuit for 4.3 seconds. Common causes include Faulty 1-2 Shift Solenoid, 1-2 Shift Solenoid harness is open or shorted, 1-2 Shift Solenoid 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: P1843 indicates 1-2 Shift Solenoid Circuit High Input Voltage.
Common causes: Common causes include Faulty 1-2 Shift Solenoid, 1-2 Shift Solenoid harness is open or shorted, 1-2 Shift Solenoid 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.

Save to My Repairs My Repairs

AI answers can be wrong. Verify repairs with testing. Open full chat

Code Popularity 19,166

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 22, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
Comments
Add Comment

💬 Need more help? Ask Coddy for instant answers — it's free!

Code P1843 Description

OBDII Code P1843 - 1-2 Shift Solenoid Circuit High Input Voltage - AutoCodes.com — P1843 Code - 1-2 Shift Solenoid Circuit High Input Voltage

What does this mean?

What are the Possible Causes of the DTC P1843?

Faulty 1-2 Shift Solenoid
1-2 Shift Solenoid harness is open or shorted
1-2 Shift Solenoid circuit poor electrical connection

How to Fix the DTC P1843?

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 P1843 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 P1843 code?

Need more information on how to fix the P1843 code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1843 code diagnosed by a professional: Find a repair shop in your area

Information for Specific Makes

P1843 Buick — 1-2 Shift Solenoid Circuit High Input Voltage
P1843 Cadillac — 1-2 Shift Solenoid Circuit High Input Voltage
P1843 Chevrolet — 1-2 Shift Solenoid Circuit High Input Voltage
P1843 GMC — 1-2 Shift Solenoid Circuit High Input Voltage
P1843 Infiniti — Automatic Transmission Fluid Pressure Switch 3
P1843 Nissan — Automatic Transmission Fluid Pressure Switch 3
P1843 Pontiac — 1-2 Shift Solenoid Circuit High Input Voltage
P1843 Saturn — 1-2 Shift Solenoid Circuit High Input 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.