AutoCodes – Lexus – C1551 Lexus

C1551 Lexus Code - Power Supply Voltage Malfunction

Quick Answer

The Power Steering ECU monitors itself for proper operation. Common causes include Power Steering ECU Fuse, Faulty Power Steering ECU, Power Steering ECU harness is open or shorted. 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: C1551 Lexus indicates Power Supply Voltage Malfunction.
Common causes: Common causes include Power Steering ECU Fuse, Faulty Power Steering ECU, Power Steering ECU harness is open or shorted.
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 1,459

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 Feb 22, 2023

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code C1551 Lexus Description

The Power Steering ECU monitors itself for proper operation. The Power Steering ECU sets the OBDII code when it detects an internal malfunction. The Power Steering ECU distinguishes the ignition switch status as ON or OFF through the IG power source circuit. The Diagnostic Trouble Code (DTC) will be set when an IG power source circuit malfunctions inside ECU.

OBDII Code C1551 Lexus - Power Supply Voltage Malfunction - AutoCodes.com — C1551 Lexus Code - Power Supply Voltage Malfunction

What does this mean?

What are the Possible Causes of the DTC C1551 Lexus?

Power Steering ECU Fuse
Faulty Power Steering ECU
Power Steering ECU harness is open or shorted
Power Steering ECU circuit poor electrical connection

How to Fix the DTC C1551 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 C1551 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 C1551 Lexus code?

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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 C1551 Lexus Code

1. What does the OBDII code C1551 mean on a Lexus?

C1551 indicates a Power Supply Voltage Malfunction in the Electronic Power Steering (EPS) system, often caused by an issue with the voltage supply to the power steering control module.

2. What are the common symptoms of code C1551 in a Lexus?

Symptoms may include a loss of power steering assist, a warning light on the dashboard, increased steering effort, or intermittent steering assistance.

3. What causes the C1551 code to appear on a Lexus?

Common causes include a weak or failing battery, loose or corroded battery terminals, a faulty power steering control module, wiring issues, or a blown fuse.

4. Can a weak battery trigger the C1551 code on a Lexus?

Yes, a weak or failing battery can cause insufficient voltage supply to the power steering system, leading to the C1551 code.

5. How can you diagnose the C1551 code on a Lexus?

Start by checking the battery voltage, inspecting battery terminals for corrosion, verifying the integrity of fuses and wiring, and using a scan tool to monitor power steering module data.

6. Can I drive my Lexus with the C1551 code?

Driving with the C1551 code is possible but not recommended, as the loss of power steering assist can make steering more difficult, especially at low speeds.

7. How do you fix the C1551 code on a Lexus?

Repairs may involve replacing the battery, cleaning or tightening battery terminals, repairing damaged wiring, replacing a blown fuse, or replacing the power steering control module if faulty.

8. Will resetting the code fix the C1551 issue on a Lexus?

Resetting the code may clear it temporarily, but the underlying issue causing the power supply voltage malfunction must be addressed to prevent it from returning.

9. How much does it cost to repair the C1551 code on a Lexus?

The cost depends on the root cause. Battery replacement can cost $100â€“$300, while power steering module repairs or replacements may cost $500â€“$1,500.

10. Can extreme weather conditions cause the C1551 code on a Lexus?

Yes, extreme cold or heat can affect battery performance and electrical connections, potentially leading to voltage issues and triggering the C1551 code.