AutoCodes – Lexus – C1740 Lexus

C1740 Lexus Code - Left Rear Height Control Solenoid Valve Circuit

Quick Answer

The Suspension Electronic Control Unit (ECU) energizes the height control solenoid valve, which opens the valve and leads compressed air to the pneumatic cylinder, thus raising the vehicle height. Common causes include Faulty Left Rear Height Control Solenoid Valve, Left Rear Height Control Solenoid Valve harness is open or shorted, Left Rear Height Control Solenoid Valve 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: C1740 Lexus indicates Left Rear Height Control Solenoid Valve Circuit.
Common causes: Common causes include Faulty Left Rear Height Control Solenoid Valve, Left Rear Height Control Solenoid Valve harness is open or shorted, Left Rear Height Control Solenoid Valve 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 817

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 Nov 19, 2020

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 C1740 Lexus Description

The Suspension Electronic Control Unit (ECU) energizes the height control solenoid valve, which opens the valve and leads compressed air to the pneumatic cylinder, thus raising the vehicle height. When the vehicle height is lowered, the ECU energizes not only the height control solenoid valve but also the exhaust valve which open the valve and discharge the compressed air in the pneumatic cylinder to the atmosphere. Front and rear height control valves have 2 solenoid valves to control right hand and left hand pneumatic cylinders separately. The exhaust valve is located on the compressor unit, and has one valve only.

OBDII Code C1740 Lexus - Left Rear Height Control Solenoid Valve Circuit - AutoCodes.com — C1740 Lexus Code - Left Rear Height Control Solenoid Valve Circuit

What does this mean?

What are the Possible Causes of the DTC C1740 Lexus?

Faulty Left Rear Height Control Solenoid Valve
Left Rear Height Control Solenoid Valve harness is open or shorted
Left Rear Height Control Solenoid Valve circuit poor electrical connection
Faulty Suspension Electronic Control Unit (ECU)

How to Fix the DTC C1740 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 C1740 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 C1740 Lexus code?

Need more information on how to fix the C1740 Lexus code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the C1740 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 C1740 Lexus Code

1. What are the common symptoms of OBDII code C1740 in a Lexus related to the Left Rear Height Control Solenoid Valve Circuit?

The common symptoms include uneven ride height, leaning to one side, and a noticeable difference in the height of the left rear side of the vehicle.

2. What are the possible causes of OBDII code C1740 in a Lexus?

Possible causes include a faulty left rear height control solenoid valve, damaged wiring or connectors in the circuit, or a malfunctioning height control module.

3. How can I diagnose the issue related to OBDII code C1740 in a Lexus?

You can diagnose the issue by conducting a visual inspection of the wiring and connectors, testing the left rear height control solenoid valve, and using an OBDII scanner to retrieve and analyze the fault code data.

4. Can I still drive my Lexus with OBDII code C1740 present?

It is not recommended to drive the vehicle with this fault code present, as it can affect the suspension system and potentially lead to further damage or safety issues.

5. How can I repair OBDII code C1740 in a Lexus related to the Left Rear Height Control Solenoid Valve Circuit?

Repair options include replacing the faulty left rear height control solenoid valve, repairing or replacing damaged wiring or connectors, and resetting the height control system.

6. Is it possible to reset the OBDII code C1740 in a Lexus without repairs?

While you can clear the fault code using an OBDII scanner, it is essential to address the underlying issue causing the code to prevent it from reoccurring.

7. How much does it typically cost to repair OBDII code C1740 in a Lexus?

The cost of repair can vary depending on the specific issue and the labor rates in your area, but it may range from a few hundred to a thousand dollars.

8. Are there any preventive maintenance tips to avoid OBDII code C1740 in a Lexus?

Regularly inspecting the suspension system, checking for signs of wear or damage, and addressing any issues promptly can help prevent the occurrence of this fault code.

9. Can a DIY enthusiast with basic automotive knowledge repair OBDII code C1740 in a Lexus?

While some repairs related to this fault code may be possible for DIY enthusiasts, it is recommended to consult a professional mechanic for a proper diagnosis and repair to ensure safety and accurate resolution.

10. How long does it typically take to repair OBDII code C1740 in a Lexus?

The repair time can vary depending on the extent of the issue and the availability of parts, but it may take a few hours to a day for a mechanic to diagnose and fix the problem.