AutoCodes – Toyota – P0117 2004 Toyota Prius

P0117 2004 Toyota Prius Code - Engine Coolant Temperature Circuit Low Input

Quick Answer

The Engine Coolant Temperature (ECT) sensor is used to detect the engine coolant temperature. Common causes include Low engine coolant level, Faulty Engine Coolant Temperature (ECT) sensor, Faulty engine coolant thermostat. 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: P0117 2004 Toyota Prius indicates Engine Coolant Temperature Circuit Low Input.
Common causes: Common causes include Low engine coolant level, Faulty Engine Coolant Temperature (ECT) sensor, Faulty engine coolant thermostat.
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 4,792

How popular is this code, among other codes? Low

Repair Importance Level

Urgent (Diagnose now) (3 / 3)

Repair Difficulty Level

Intermediate (2 / 3)

What is this?

Table of contents Created and updated by William Orellana on Jun 14, 2020

Description
Possible Causes
How To Fix
Tech Notes
Cost to Diagnose
FAQs
Comments
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Code P0117 2004 Toyota Prius Description

The Engine Coolant Temperature (ECT) sensor is used to detect the engine coolant temperature. The sensor modifies a voltage signal from the Engine Control Module (ECM). The modified signal returns to the ECM as the engine coolant temperature input. The sensor uses a thermistor which is sensitive to the change in temperature. The electrical resistance of the thermistor decreases as temperature increases.

OBDII Code P0117 2004 Toyota Prius - Engine Coolant Temperature Circuit Low Input - AutoCodes.com — P0117 2004 Toyota Prius Code - Engine Coolant Temperature Circuit Low Input

What does this mean?

What are the Possible Causes of the DTC P0117 2004 Toyota Prius?

Low engine coolant level
Faulty Engine Coolant Temperature (ECT) sensor
Faulty engine coolant thermostat
Engine Coolant Temperature (ECT) sensor harness is open or shorted
Engine Coolant Temperature (ECT) sensor circuit poor electrical connection

How to Fix the DTC P0117 2004 Toyota Prius?

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

If there are no coolant leaks, replace the thermostat first, if problem is still there check/replace coolant temperature sensor.

What is the Cost to Diagnose the Code?

Labor: 1.0

To diagnose the P0117 2004 Toyota Prius 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 P0117 2004 Toyota Prius code?

Need more information on how to fix the P0117 2004 Toyota Prius 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 P0117 2004 Toyota Prius Code

1. What are the common symptoms of OBDII code P0117 on a 2004 Toyota Prius?

The common symptoms of code P0117 on a 2004 Toyota Prius include a high engine temperature reading on the dashboard, poor fuel economy, rough idling, and potential stalling.

2. What does the OBDII code P0117 Engine Coolant Temperature Circuit Low Input mean for a 2004 Toyota Prius?

The P0117 code indicates that the Engine Control Module (ECM) has detected a lower than normal voltage signal from the Engine Coolant Temperature (ECT) sensor.

3. What are the possible causes of the P0117 code on a 2004 Toyota Prius?

Common causes of the P0117 code on a 2004 Toyota Prius include a faulty ECT sensor, damaged wiring or connectors in the ECT circuit, low coolant levels, or a malfunctioning ECM.

4. How can I diagnose the P0117 code on my 2004 Toyota Prius?

Diagnosing the P0117 code involves checking the ECT sensor for proper resistance values, inspecting the wiring for any damage, verifying coolant levels, and testing the ECM for functionality using a scan tool.

5. Can I continue driving my 2004 Toyota Prius with the P0117 code present?

It is not recommended to drive your Prius with the P0117 code active, as it can lead to poor engine performance, potential overheating, and other serious issues that may cause further damage.

6. How can I repair the P0117 code on my 2004 Toyota Prius?

To repair the P0117 code, you may need to replace the ECT sensor, repair any damaged wiring or connectors, top up coolant levels, or reprogram the ECM if necessary.

7. Will resetting the fault codes make the P0117 code disappear on my 2004 Toyota Prius?

Resetting the fault codes may temporarily clear the P0117 code, but if the underlying issue is not addressed, the code is likely to reappear once the ECM detects the problem again.

8. Is the P0117 code a serious issue on a 2004 Toyota Prius?

The P0117 code should be addressed promptly to prevent potential engine damage or performance issues. Ignoring the code can lead to overheating, reduced fuel efficiency, and other problems.

9. Can a DIY enthusiast fix the P0117 code on a 2004 Toyota Prius?

Depending on your skill level and access to tools, a DIY enthusiast may be able to diagnose and address the P0117 code by following repair guides and using appropriate diagnostic equipment.

10. How much does it typically cost to repair the P0117 code on a 2004 Toyota Prius at a mechanic?

The cost of repairing the P0117 code on a 2004 Toyota Prius can vary depending on the exact cause of the issue, but it may range from around $100 to $300 for parts and labor at a mechanic.