Q21-6007S | Genuine Paccar® Engine Coolant Level Sensor

Description: An Engine Coolant Level Sensor Q21-6007S is a small electronic sensor that monitors the amount of coolant inside the radiator or coolant reservoir. Its job is to alert the driver if the engine’s coolant level becomes too low, helping prevent overheating and engine damage. Part Number: Q21-6007S, Q216007S Condition: New Manufacture/Brand: Paccar Fits Q21-6007S For  Cummins QSK50 QSK60 Q21-6007S Diesel Engine Pbt-Gp30 Construction Machinery Excavator Kenworth Peterbilt Purpose of using Q21-6007S:   1. Detects Coolant Level Measures whether the coolant in the tank or radiator is at the proper height. 2. Sends a Signal to the Car’s Computer If the coolant drops below a safe level, it notifies the Engine Control Module (ECM) or instrument cluster. 3. Triggers Dashboard Warning Light Activates a “Low Coolant” or “Check Coolant Level” warning on the dashboard. 4. Helps Prevent Overheating Low coolant can cause the engine to overheat. The sensor acts as an early warning system before serious engine damage occurs.   Signs of a Bad Engine Coolant Level Sensor Q21-6007S: 1. “Low Coolant” Warning Light Stays On The dashboard warning appears even when the coolant reservoir is full. This is the most common symptom of a faulty sensor. 2. “Low Coolant” Warning Comes On and Off Randomly The light may flicker or activate only on bumps or sharp turns. Often caused by a sensor that’s dirty, sticking, or failing internally. 3. No Warning When Coolant Is Actually Low A dangerous symptom. The sensor fails to alert you, which can lead to engine overheating. 4. Overheating Without a Coolant Warning If the sensor doesn’t detect low coolant, the engine may overheat without any early indication. 5. Faulty or Inconsistent Readings The sensor may send incorrect or unstable signals to the ECM or instrument cluster. A scan tool might show erratic coolant level messages. 6. Check Engine Light (Less Common) Some vehicles may set a diagnostic code if the coolant level signal is missing or invalid. 7. Corroded or Damaged Sensor Connector Wiring or connector damage can mimic a bad sensor. May cause intermittent or weak signals.   About the Manufacturer – Paccar: PACCAR Inc is a global technology leader in the design, manufacture, and customer support of premium light-, medium-, and heavy-duty trucks. Founded in 1905 and headquartered in Bellevue, Washington, PACCAR is best known for its world-class truck brands: Kenworth, Peterbilt, and DAF. PACCAR’s trucks are recognized for their durability, fuel efficiency, advanced engineering, and driver-focused technology. In addition to truck manufacturing, PACCAR also designs and builds diesel engines, and provides financial services, information technology, and aftermarket support to its global customer base.