NTC Automotive Water Temperature Sensor bmw 13621433076 10026418 1433076 MEK000030 MEK100170 MEK500130

The water temperature sensor operates based on the principles of resistance and thermistor technology. As an NTC (Negative Temperature Coefficient) sensor, it exhibits the following resistance behavior:

• Low coolant temperature → High resistance → High voltage signal to ECU

• High coolant temperature → Low resistance → Low voltage signal to ECU

The ECU supplies a voltage on the 5-volt reference circuit to the sensor. As the temperature of the coolant changes, the resistance value of the sensor changes accordingly. This change in resistance is then converted into a voltage signal that the ECU reads. The ECU uses this data to make adjustments to the engine's performance, allowing it to operate at an optimal temperature.

The Water Temperature Sensor (Part No. 10026418) is an OE-grade component with multiple recognized reference numbers across different platforms.

This sensor meets automotive industry safety and performance standards, guaranteeing reliability equivalent to original equipment.

The 10026418 water temperature sensor is designed for compatibility with a range of vehicle platforms across multiple manufacturers.

The sensor is also compatible with a wide range of BMW models, including but not limited to:

Important: Always verify connector type, thread size, and vehicle compatibility with your specific application before purchase. Providing the Vehicle Identification Number (VIN) when ordering ensures the part fits your vehicle correctly.

A failing or faulty water temperature sensor can manifest through various drivability and performance issues. Early recognition of these symptoms can prevent more serious engine damage and costly repairs.

A faulty sensor may cause the water temperature gauge to malfunction. The indicator needle may either not move at all or point directly to the highest position, indicating that the sensor cannot read temperature information correctly.

Because the water temperature sensor cannot provide an accurate water temperature signal, the ECU cannot properly adjust the air-fuel mixture concentration. This results in a mixture that is too lean during cold starts, making it difficult to start the engine.

Failure of the water temperature sensor may lead to increased fuel consumption. When the sensor provides inaccurate temperature data, the ECU may incorrectly adjust fuel delivery, often resulting in a richer-than-necessary air-fuel mixture.

A faulty sensor can cause unstable idle speed. The engine may idle roughly or inconsistently due to incorrect fuel delivery calculations.

A malfunctioning sensor can cause difficulty during acceleration. Inaccurate temperature data can disrupt the ECU's calculations for ignition timing and fuel delivery.

The instrument panel water temperature warning light may illuminate, indicating a problem with the cooling system or the sensor itself.

The ECU detects abnormal resistance values or signal patterns from the sensor and stores corresponding Diagnostic Trouble Codes (DTCs).

If the sensor fails to detect rising coolant temperatures accurately, the ECU may not activate the cooling fan at the appropriate time. This can lead to engine overheating — one of the most serious consequences of sensor failure.

Inaccurate temperature data can result in reduced engine power, rough idling, or hesitation during acceleration. If the water temperature sensor fails, it may lead to decreased engine performance and even cause engine failure.

Visual inspection may reveal:

• Cracks in the sensor housing

• Coolant leaks around the sensor mounting area

• Corrosion on electrical connectors

• Damaged or frayed wiring

When purchasing a replacement water temperature sensor (Part No. 10026418), the following factors should be carefully evaluated to ensure proper fitment, reliable performance, and long service life.

Before purchasing, confirm that the sensor displays the correct part number (10026418) or one of its equivalent numbers (MG10026418, 13621433076, 1433076, 23017838935, MEK000030, MEK000030L). Multiple OE numbers may reference the same component specification — verifying these numbers helps ensure you receive the correct part for your application.

The 10026418 sensor is compatible with a wide range of vehicles including:

• SAIC MG (GT, MG3, MG ZS, MG-5)

• SAIC MAXUS (G10)

• Roewe (荣威)

• BMW (selected models)

Always cross-reference with your vehicle's specific year, make, model, and engine displacement. Providing the VIN number when ordering ensures the part fits your vehicle correctly.

Before purchasing, confirm that the sensor's electrical connector type matches your vehicle's wiring harness. Connector mismatch is one of the most common installation issues encountered during replacement.

Opt for sensors manufactured to OE specifications. A high-quality sensor provides:

• Enhanced resistance to thermal degradation

• Superior protection against coolant corrosion

• Longer operational lifespan

• Reliable temperature readings with long-term stability

The 10026418 sensor typically comes with a 12-month warranty. When purchasing from a supplier, verify the warranty terms and conditions. Quality sensors should be backed by appropriate warranty protection against manufacturing defects.

The 10026418 sensor is manufactured in China. When purchasing, verify that the supplier provides clear product specifications and proper packaging to prevent damage during shipping.

When replacing a faulty water temperature sensor, it is advisable to inspect related cooling system components:

• Upper and lower coolant hoses for cracks, leaks, or deterioration

• Radiator for cracks, leaks, or damage

• Radiator cap for proper sealing

• Coolant level and condition

• Cooling fan operation

Always refer to the vehicle owner's manual for the correct coolant type and replacement procedure.

Before installing the new sensor:

• Inspect the wiring harness connector for corrosion, damage, or loose pins

• Check for broken or frayed wires

• Clean connector terminals if necessary

• Ensure a secure, weather-tight connection upon installation

While the symptoms listed above can indicate a faulty water temperature sensor, many of these symptoms can also be caused by other issues such as:

• Faulty coolant thermostat

• Wiring harness problems

• ECU issues

• Cooling system leaks

• Cooling fan motor failure

It is recommended to have the vehicle properly diagnosed using a scan tool to read stored DTCs before replacing the sensor. This ensures that the sensor is indeed the root cause of the symptoms and prevents unnecessary parts replacement.

• Allow the engine to cool completely before attempting sensor removal or installation to prevent burns from hot coolant

• Apply a small amount of thread sealant (compatible with coolant systems) if required

• Tighten the sensor to the manufacturer's specified torque value (avoid over-tightening, which can damage the sensor or the mounting point)

• After installation, check coolant level and top up if necessary

• Start the engine and check for leaks around the sensor mounting area

• Verify that the temperature gauge operates correctly and the Check Engine Light (if illuminated) has been cleared

If the sensor is not installed immediately, store it in a cool, dry environment away from direct sunlight and moisture. Avoid dropping or subjecting the sensor to mechanical shock, as this can damage the internal sensing element.

Real-time Temperature Monitoring: The water temperature sensor monitors the coolant temperature in real time to ensure the stable working temperature of the engine. Only when the engine operates within an appropriate temperature range can it run efficiently. During the cold start phase, it transmits the low-temperature signal to the control unit, which adjusts the fan speed and increases the idle speed to accelerate the engine warming process. When the engine temperature is too high, it triggers the fan to operate at high speed to promptly cool the engine.

Fuel Injection and Ignition Timing Correction: The temperature signal transmitted by the water temperature sensor is an important reference for the fuel injection system and ignition system. In cold environments, the engine needs a richer mixture to start smoothly. The sensor feedbacks the low-temperature signal to the control unit, which increases the fuel injection volume and appropriately increases the ignition advance angle. When the engine reaches the normal working temperature, it prompts the control unit to adjust the fuel injection volume and ignition timing, allowing for more complete fuel combustion.

Dashboard Gauge Data: The water temperature sensor synchronously transmits the real-time monitored temperature signal to the water temperature gauge on the vehicle dashboard. By observing the reading, the owner can intuitively understand the working temperature of the engine.

Common failure modes include:

• Condensation damage – Moisture ingress can cause internal corrosion

• Electrical connection failure – Corroded or loose connector pins

• Internal thermistor failure – Open or short circuit conditions

• Physical damage – Cracks from thermal stress or mechanical impact