AutoCodes – Lexus – P0A71 Lexus

P0A71 Lexus Code - Generator Phase U Current High

Quick Answer

The inverter converts the high-voltage direct current of the HV battery and the alternating current for the MG1/MG2. Common causes include Faulty Inverter With Converter Assembly, Inverter With Converter Assembly harness is open or shorted, Inverter With Converter Assembly 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: P0A71 Lexus indicates Generator Phase U Current High.
Common causes: Common causes include Faulty Inverter With Converter Assembly, Inverter With Converter Assembly harness is open or shorted, Inverter With Converter Assembly 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 1,222

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 May 11, 2019

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

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

Code P0A71 Lexus Description

The inverter converts the high-voltage direct current of the HV battery and the alternating current for the MG1/MG2. The inverter contains a three-phase bridge circuit, which consists of 6 power transistors each for the MG1 and the MG2, in order to convert the direct current and the three-phase alternating current.
The HV control ECU controls the actuation of the power transistors.
The inverter transmits information that is necessary for effecting control, such as the amperage and voltage, to the HV control ECU.
The motor inverter current sensors detect the amperage that flows through the V and W phase cables between the inverter and MG1/MG2. The inverter transmits information that is necessary for effecting control, such as the amperage and voltage, to the HV control ECU.
The HV control ECU monitors the inverter current sensors to detect a malfunction in the sensor system.

OBDII Code P0A71 Lexus - Generator Phase U Current High - AutoCodes.com — P0A71 Lexus Code - Generator Phase U Current High

What does this mean?

What are the Possible Causes of the DTC P0A71 Lexus?

Faulty Inverter With Converter Assembly
Inverter With Converter Assembly harness is open or shorted
Inverter With Converter Assembly circuit poor electrical connection

How to Fix the DTC P0A71 Lexus?

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 P0A71 Lexus 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 P0A71 Lexus code?

Need more information on how to fix the P0A71 Lexus code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P0A71 Lexus code diagnosed by a professional: Find a repair shop in your area

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.

Frequently Asked Questions about P0A71 Lexus Code

1. What does the OBDII code P0A71 mean for a Lexus?

P0A71 indicates "Generator Phase U Current High," meaning the hybrid vehicle's generator has detected an abnormally high electrical current in phase U of the motor-generator system.

2. What are the common symptoms of the P0A71 code on a Lexus?

Symptoms may include an illuminated check engine light, reduced hybrid system performance, limited power output, or the vehicle entering "limp mode."

3. What causes the P0A71 code to trigger on a Lexus?

Possible causes include a malfunctioning motor-generator, a short circuit in the wiring, a faulty inverter assembly, or an issue with the hybrid system control module.

4. Can I drive my Lexus with the P0A71 code active?

It is not recommended to drive the vehicle for extended periods, as this code indicates a potential issue with the hybrid system that could lead to further damage or reduced performance.

5. How is the P0A71 code diagnosed on a Lexus?

A technician will use a scan tool to verify the code, inspect the generator motor and associated wiring, test the inverter assembly, and check for any additional error codes.

6. What are the repair options for the P0A71 code on a Lexus?

Repairs may include replacing faulty wiring, repairing or replacing the generator motor, servicing the inverter assembly, or updating the hybrid control module software.

7. How much does it cost to fix the P0A71 code on a Lexus?

Repair costs vary widely depending on the root cause, ranging from $200 for minor wiring repairs to over $2,000 for replacing the inverter or generator components.

8. Can a weak hybrid battery cause the P0A71 code on a Lexus?

While unlikely, a weak or failing hybrid battery may contribute to abnormal electrical current levels, potentially triggering this code.

9. How can I prevent the P0A71 code from occurring on my Lexus?

Regular maintenance of the hybrid system, including inspections of the inverter and generator components, can help prevent issues leading to this code.

10. Is the P0A71 code specific to Lexus hybrid models?

Yes, this code is specific to hybrid vehicles, particularly those with motor-generator systems, and is most commonly seen in Lexus hybrid models.