AutoCodes – Toyota – P0657 2006 Toyota Highlander

P0657 2006 Toyota Highlander Code - Actuator Supply Voltage Circuit Open

Quick Answer

The Engine Control Module (ECM) continuously monitors its internal memory status, internal circuits, and output signals to the throttle actuator. Common causes include Faulty Engine Control Module (ECM), Engine Control Module harness is open or shorted, Engine Control Module 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: P0657 2006 Toyota Highlander indicates Actuator Supply Voltage Circuit Open.
Common causes: Common causes include Faulty Engine Control Module (ECM), Engine Control Module harness is open or shorted, Engine Control Module 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 2,107

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 Jan 25, 2019

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0657 2006 Toyota Highlander Description

The Engine Control Module (ECM) continuously monitors its internal memory status, internal circuits, and output signals to the throttle actuator. This self−check insures that the ECM is functioning properly. If any malfunction is detected, the ECM will set the code and illuminate the engine light.
The ECM memory status is diagnosed by internal mirroring of the main CPU and the sub CPU to detect Random Access Memory (RAM) errors. The two CPUs also perform continuous mutual monitoring. The ECM illuminates the MIL and sets a DTC if: 1) outputs from the two CPUs are different or deviate from the standards, 2) the signals sent to the throttle actuator deviate from the standards, 3) a malfunction is found in the throttle actuator supply voltage, and 4) any other ECM malfunction is found.

OBDII Code P0657 2006 Toyota Highlander - Actuator Supply Voltage Circuit Open - AutoCodes.com — P0657 2006 Toyota Highlander Code - Actuator Supply Voltage Circuit Open

What does this mean?

What are the Possible Causes of the DTC P0657 2006 Toyota Highlander?

Faulty Engine Control Module (ECM)
Engine Control Module harness is open or shorted
Engine Control Module circuit poor electrical connection
Engine Control Module Programming update

How to Fix the DTC P0657 2006 Toyota Highlander?

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 does this mean?

Code Tech Notes

Check the ECM fuse, if fuse is OK try erasing the code first and if the code comes back you may have to reprogram or replaced the ECM.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0657 2006 Toyota Highlander 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 P0657 2006 Toyota Highlander code?

Need more information on how to fix the P0657 2006 Toyota Highlander code? Get Access to Factory Service Manuals

Need Help with the 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 P0657 2006 Toyota Highlander Code

1. What does the OBDII code P0657 mean on a 2006 Toyota Highlander?

P0657 indicates an issue with the actuator supply voltage circuit, specifically that it is open or has a fault, potentially affecting various engine or transmission components.

2. What are the common symptoms of code P0657 in a 2006 Toyota Highlander?

Symptoms may include poor engine performance, transmission shifting issues, illuminated check engine light, or loss of power to certain vehicle systems.

3. What causes the P0657 code in a 2006 Toyota Highlander?

Common causes include damaged wiring or connectors in the actuator supply voltage circuit, a faulty actuator or control module, or a blown fuse.

4. Can a damaged actuator cause the P0657 code to appear?

Yes, a malfunctioning actuator connected to the supply voltage circuit can trigger the P0657 code.

5. How do you diagnose the P0657 code in a 2006 Toyota Highlander?

Diagnosis involves checking the wiring, connectors, and fuses for damage, testing the actuator supply voltage circuit for continuity, and inspecting the control module for faults.

6. Is it safe to drive a 2006 Toyota Highlander with code P0657?

Driving with this code is not recommended, as it can lead to performance issues, transmission malfunctions, or further damage to the vehicle.

7. What tools are needed to troubleshoot the P0657 code?

Basic tools include a multimeter to test voltage and continuity, an OBDII scanner for retrieving and clearing codes, and a wiring diagram for the actuator circuit.

8. Can a blown fuse cause the P0657 code in a 2006 Toyota Highlander?

Yes, a blown fuse in the actuator supply voltage circuit can interrupt power and trigger this code.

9. How is the P0657 code fixed in a 2006 Toyota Highlander?

Repairs may involve replacing damaged wiring or connectors, replacing the faulty actuator or control module, or replacing a blown fuse.

10. How much does it cost to fix the P0657 code on a 2006 Toyota Highlander?

The repair cost depends on the root cause. Wiring repairs may cost $100-$300, while actuator or module replacement can range from $300 to $800 or more.