AutoCodes – Toyota – P1790 2001 Toyota Echo

P1790 2001 Toyota Echo Code - ST Solenoid Valve Circuit Malfunction

Quick Answer

Shift solenoid valve ST is switched ON-OFF by a signal from ECM so that let in or out timing of 2nd brake is adjusted by operating orifice control valve. Common causes include Open or short in shift solenoid valve ST circuit, Shift solenoid valve ST. 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: P1790 2001 Toyota Echo indicates ST Solenoid Valve Circuit Malfunction.
Common causes: Common causes include Open or short in shift solenoid valve ST circuit, Shift solenoid valve ST.
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 2,598

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 Sep 19, 2019

Description
Possible Causes
How To Fix
Cost to Diagnose
FAQs
Comments
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Code P1790 2001 Toyota Echo Description

Shift solenoid valve ST is switched ON-OFF by a signal from ECM so that let in or out timing of 2nd brake is adjusted by operating orifice control valve. Therefore, shift solenoid valve ST operates when letting in or out reverse clutch. f it is broken, the shift shock becomes big.

OBDII Code P1790 2001 Toyota Echo - ST Solenoid Valve Circuit Malfunction - AutoCodes.com — P1790 2001 Toyota Echo Code - ST Solenoid Valve Circuit Malfunction

What does this mean?

What are the Possible Causes of the DTC P1790 2001 Toyota Echo?

Open or short in shift solenoid valve ST circuit
Shift solenoid valve ST

How to Fix the DTC P1790 2001 Toyota Echo?

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 P1790 2001 Toyota Echo 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 P1790 2001 Toyota Echo code?

Need more information on how to fix the P1790 2001 Toyota Echo code? Get Access to Factory Service Manuals

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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 P1790 2001 Toyota Echo Code

1. What does the OBDII code P1790 on a 2001 Toyota Echo indicate?

- The code P1790 indicates a malfunction in the ST Solenoid Valve circuit in the transmission.

2. What are the common symptoms of a P1790 code in a 2001 Toyota Echo?

- Common symptoms include harsh shifting, transmission slipping, or the transmission going into "limp mode."

3. What are the possible causes of a P1790 code on a 2001 Toyota Echo?

- Possible causes include a faulty ST Solenoid Valve, damaged wiring or connectors in the circuit, or a malfunctioning transmission control module.

4. How can I diagnose the P1790 code on my 2001 Toyota Echo?

- To diagnose the issue, you can use an OBDII scanner to read the code, inspect the wiring and connectors related to the ST Solenoid Valve, and perform a thorough transmission fluid check.

5. Can I continue driving my 2001 Toyota Echo with a P1790 code?

- It is not recommended to drive the vehicle with a P1790 code, as it can lead to further damage to the transmission if left unresolved.

6. How can I repair a P1790 code on a 2001 Toyota Echo?

- Repair options include replacing the ST Solenoid Valve, repairing any damaged wiring or connectors, or reprogramming the transmission control module.

7. Will resetting the OBDII code P1790 on a 2001 Toyota Echo solve the issue?

- Resetting the code may temporarily clear the warning light, but it will not fix the underlying issue causing the P1790 code.

8. How much does it cost to repair a P1790 code on a 2001 Toyota Echo?

- The cost of repair can vary depending on the exact cause of the issue, but it may range from a few hundred to over a thousand dollars, including parts and labor.

9. Can a DIY enthusiast repair a P1790 code on a 2001 Toyota Echo?

- While some DIY enthusiasts may have the skills to tackle this repair, dealing with transmission-related issues can be complex, and it is often recommended to seek professional help.

10. How can I prevent the recurrence of a P1790 code on my 2001 Toyota Echo?

- Regular maintenance, such as checking and changing transmission fluid as recommended, can help prevent issues like the P1790 code from occurring.