AutoCodes – Mazda – P1289 Mazda

P1289 Mazda Code - Cylinder Head Temperature Sensor Signal Greater Than Self-Test Range

Quick Answer

The Cylinder Head Temperature (CHT) Sensor is mounted into the wall of the cylinder head and is not connected to any coolant passages. Common causes include Wrong thermostat, Not at operating range, Engine overheated. 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: P1289 Mazda indicates Cylinder Head Temperature Sensor Signal Greater Than Self-Test Range.
Common causes: Common causes include Wrong thermostat, Not at operating range, Engine overheated.
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 10,993

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 Aug 07, 2019

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 P1289 Mazda Description

The Cylinder Head Temperature (CHT) Sensor is mounted into the wall of the cylinder head and is not connected to any coolant passages. The CHT sends a signal to the Powertrain Control Module (PCM) indicating the cylinder head temperature. If the temperature exceeds 126°C (-258°F), the PCM disables four fuel injectors at a time. The PCM will alternate which four injectors are disabled every 32 engine cycles. The four cylinders that are not being fuel injected act as air pumps to aid in cooling the engine. If the temperature exceeds 154 °C (310°F), the PCM disables all of the fuel injectors until the engine temperature drops below 154°C (310°F).

OBDII Code P1289 Mazda - Cylinder Head Temperature Sensor Signal Greater Than Self-Test Range - AutoCodes.com — P1289 Mazda Code - Cylinder Head Temperature Sensor Signal Greater Than Self-Test Range

What does this mean?

What are the Possible Causes of the DTC P1289 Mazda?

Wrong thermostat
Not at operating range
Engine overheated
Low engine coolant level
Faulty Cylinder Head Temperature (CHT) sensor
Cylinder Head Temperature (CHT) sensor harness is open or shorted
Cylinder Head Temperature (CHT) sensor circuit poor electrical connection

How to Fix the DTC P1289 Mazda?

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 P1289 Mazda 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 P1289 Mazda code?

Need more information on how to fix the P1289 Mazda code? Get Access to Factory Service Manuals

Need Help with the Code?

Get the P1289 Mazda 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 P1289 Mazda Code

1. What does the OBDII code P1289 mean on a Mazda?

P1289 indicates that the cylinder head temperature (CHT) sensor is detecting a temperature signal outside the expected range during the self-test.

2. What are the common symptoms of code P1289 in a Mazda?

Symptoms may include engine overheating, poor performance, rough idle, or the engine going into fail-safe or limp mode to prevent damage.

3. What causes the P1289 code to appear on a Mazda?

Possible causes include a faulty CHT sensor, damaged wiring or connectors, a stuck thermostat, low coolant levels, or a malfunctioning engine control module (ECM).

4. How does the cylinder head temperature sensor function in a Mazda?

The CHT sensor monitors the engine's temperature by measuring the heat of the cylinder head and sends this data to the ECM to regulate engine performance.

5. Can I drive my Mazda with a P1289 code?

Driving with a P1289 code is not recommended, as it could indicate engine overheating, which can cause severe engine damage if not addressed promptly.

6. How can I diagnose the P1289 code in my Mazda?

Begin by checking the CHT sensor and its wiring for damage, ensure the coolant level is adequate, verify the thermostat is functioning, and use a scan tool to monitor live temperature data.

7. How do I fix the P1289 code on a Mazda?

Repairs may involve replacing the CHT sensor, repairing damaged wiring or connectors, flushing and refilling coolant, or replacing the thermostat if it's stuck.

8. Is a P1289 code always caused by a bad cylinder head temperature sensor?

No, the issue could also stem from wiring problems, a coolant system issue, or a faulty ECM, so thorough diagnosis is essential.

9. How much does it cost to repair a P1289 code on a Mazda?

The cost can vary depending on the cause. Replacing a CHT sensor typically costs $50-$150 for parts and labor, while other repairs, like thermostat replacement, may cost more.

10. Can low coolant levels trigger a P1289 code on a Mazda?

Yes, low coolant levels can cause the engine to overheat, leading to abnormal temperature readings and triggering the P1289 code.