AutoCodes – Lexus – C1738 Lexus

C1738 Lexus Code - Left Front 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 Front Height Control Solenoid Valve, Left Front Height Control Solenoid Valve harness is open or shorted, Left Front 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: C1738 Lexus indicates Left Front Height Control Solenoid Valve Circuit.
Common causes: Common causes include Faulty Left Front Height Control Solenoid Valve, Left Front Height Control Solenoid Valve harness is open or shorted, Left Front 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.

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Code Popularity 1,189

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
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Code C1738 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 C1738 Lexus - Left Front Height Control Solenoid Valve Circuit - AutoCodes.com — C1738 Lexus Code - Left Front Height Control Solenoid Valve Circuit

What does this mean?

What are the Possible Causes of the DTC C1738 Lexus?

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

How to Fix the DTC C1738 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 C1738 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 C1738 Lexus code?

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Need Help with the Code?

Get the C1738 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 C1738 Lexus Code

1. What are the common symptoms of OBDII code C1738 in a Lexus related to the Left Front Height Control Solenoid Valve Circuit?

The common symptoms include uneven ride height, leaning to one side, or abnormal suspension behavior.

2. What could cause the OBDII code C1738 in a Lexus to trigger?

The code C1738 may be triggered by a faulty left front height control solenoid valve, wiring issues, or a problem with the suspension system.

3. How can I diagnose the cause of OBDII code C1738 in my Lexus?

To diagnose the issue, you can perform a visual inspection of the wiring, test the left front height control solenoid valve, and check the suspension components for any damage.

4. Can I drive my Lexus with OBDII code C1738 present?

It is not recommended to drive your Lexus with code C1738 present, as it can lead to further damage to the suspension system and affect the vehicle's handling.

5. What are some repair tips for fixing OBDII code C1738 in a Lexus?

Repair tips include checking and repairing any damaged wiring, replacing the left front height control solenoid valve if necessary, and ensuring proper functioning of the suspension system.

6. How much does it cost to repair OBDII code C1738 in a Lexus?

The cost of repair can vary depending on the exact cause of the code, but it may involve expenses for parts and labor, ranging from a few hundred to over a thousand dollars.

7. Can I reset OBDII code C1738 in my Lexus by disconnecting the battery?

While disconnecting the battery may clear the code temporarily, it is not a recommended long-term solution. It's best to diagnose and fix the underlying issue to prevent the code from reoccurring.

8. Is it possible to prevent OBDII code C1738 in a Lexus from triggering again in the future?

Regular maintenance of the suspension system, checking the wiring for any signs of wear, and addressing any issues promptly can help prevent the code C1738 from triggering in the future.

9. How serious is OBDII code C1738 in a Lexus?

Code C1738 can impact the vehicle's handling and stability, so it's important to address the issue promptly to avoid further damage to the suspension system.

10. Can a DIY enthusiast repair OBDII code C1738 in a Lexus, or is it best left to professionals?

While some aspects of diagnosing and repairing code C1738 can be tackled by a knowledgeable DIY enthusiast, it's recommended to consult with a professional mechanic for proper diagnosis and repair to ensure the issue is resolved correctly.