Purpose

This VT‑YBK902 coolant water level sensor is specially developed for buses and coaches. It is installed on the expansion water tank of the engine cooling system to real‑time detect the coolant liquid level. When the cooling water is insufficient, it will send out alarm signal to the bus instrument panel, reminding drivers to add coolant in time. It effectively avoids engine overheating, cylinder burning and other failures caused by water shortage, and guarantees safe operation of passenger vehicles.

Product Features

Adopts high‑quality brass sensing body with strong structural rigidity. Equipped with integrated PVC wiring harness and waterproof plug‑in connector for stable signal transmission. Designed for harsh working environment of commercial vehicles, it can adapt to large temperature changes inside the engine compartment. Compact overall structure, dedicated thread size for bus water tank, convenient for matching and replacement.

Product Advantages

1. High sensitivity for liquid‑level induction, rapid response when coolant level drops.

2. Excellent waterproof and anti‑corrosion performance, long service life under vibration environment.

3. Low failure rate, stable output signal, no false alarm.

4. Direct plug‑and‑play design, no extra modification required for most bus models.

5. Strictly tested for commercial vehicle standards, suitable for long‑time continuous working.

Installation Method

1. Make sure the engine is completely cooled down, release residual pressure inside the expansion tank before installation.

2. Screw off the old sensor from the thread hole of expansion water tank.

3. Screw the new VT‑YBK902 sensor clockwise into the threaded hole of water tank, tighten properly, do not apply excessive force to avoid thread damage.

4. Connect the waterproof harness connector to the corresponding vehicle wiring plug.

5. Fill coolant to normal liquid level, power on the bus, check whether the sensor alarm function works normally.

Notes

1. Installation must be carried out under cold engine status. Hot coolant may cause scald injury. Never disassemble when the engine is hot.

2. Do not over‑tighten the sensor thread, brass thread is easy to crack under excessive torque.

3. Keep the harness and connector away from high‑temperature exhaust parts to prevent cable aging and melting.

4. Regularly check for water seepage at threaded joint. Replace sensor immediately if leakage occurs.

5. Use qualified coolant, avoid impurity sediment sticking on sensor probe, which will cause signal error or false alarm.

6. Do not pull or drag the wiring harness forcibly during installation and maintenance.