Engine-Codes - Kia - P0731 KIA

P0731 KIA Code - First Gear Incorrect Ratio

- Code Popularity: 18,073 Views
- Repair Importance Level: 3/3
- Repair Difficulty Level: 3/3
Table of contents

|What are the Possible Causes of the Code P0731 KIA?

  • Low transmission fluid level
  • Dirty transmission fluid
  • Shift solenoids
  • Transmission mechanical problems
  • Transmission hydraulic control circuit

|How to Fix the P0731 KIA Code?

Start by checking the "Possible Causes" listed above. Visually inspect the related wiring harness and connectors. Check for damaged components and look for broken, bent, pushed out, or corroded connector's pins.

|Code P0731 KIA Tech Notes

Start by inspecting the transmission fluid level and condition, and change fluid if necessary.

|What is the Cost to Diagnose the Code P0731 KIA?

Labor: 1.0

The cost to diagnose the P0731 KIA code is 1.0 hour of labor. The auto repair's diagnosis time and labor rates vary by location, vehicle's make and model, and even your engine type. Most auto repair shops charge between $75 and $150 per hour.

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|When is the P0731 KIA Code Detected?

P0731 is detected when A/T cannot be shifted to the 1st gear position even if electrical circuit is good.

|What are Code P0731 KIA Possible Symptoms?

  • Engine Light ON (or Service Engine Soon Warning Light)
  • Incorrect transmission shifting

|What Does the P0731 KIA Code Mean?

This diagnosis monitors actual gear position by checking the torque converter slip ratio calculated by Transmission Control Module (TCM) as follows:

Torque converter slip ratio = A x C/B
A: Output shaft revolution signal from revolution sensor
B: Engine speed signal from Engine Control Module (ECM)
C: Gear ratio determined as gear position which TCM supposes

If the actual gear position is higher than the position (1st) supposed by TCM, the slip ratio will be more than normal. In case the ratio exceeds the specified value, TCM judges this diagnosis malfunction.

First Gear Incorrect Ratio

|Need more Information on the P0731 KIA Code?

Need more information on how to fix the P0731 KIA code? Get Access to Factory Service Manuals

|Need Help with the P0731 KIA Code?

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