Why does the car's water temperature always stay at 0?

[AdalineFitz]

Confirm that the radiator is not short of water. Here are the specific details: 1. Water temperature gauge: Especially for older analog pointer-type water temperature gauges, the bottom of the scale is not '0' degrees Celsius but approximately 40-50 degrees. This means that unless the temperature exceeds 40-50 degrees, you won't see the pointer move. So, it's possible that after 'starting the engine for a long time,' the water temperature hasn't reached 50 degrees, but it 'staying at 0' is impossible. You can use a Bluetooth OBD adapter to directly read the water temperature value from the ECU, which is much more accurate than the dashboard and provides a digital reading, eliminating the need for guesswork. 2. Solution: Monitor the engine oil temperature to determine the engine's operating condition. If the oil temperature is very high (around 110-120 degrees) but the water temperature hasn't risen, there might be an issue with the coolant circulation. Check if hot water is flowing into the upper radiator hose. If hot water is being injected but the temperature remains low, inspect the temperature sensor, wiring connectors, and dashboard.

[LaSavannah]

When the temperature gauge in your car consistently shows 0 degrees while driving, it usually indicates a fault with the coolant temperature sensor or its wiring. The sensor monitors the engine temperature and sends data to the dashboard. If the sensor is damaged, has poor contact, or is clogged with dirt, the signal cannot be transmitted, causing the display to stick at 0. Wiring issues such as loose connectors, short circuits, or broken wires can also cause this, with a blown fuse being a common trigger—unstable current can easily cause it to burn out. Dashboard malfunctions are rare but possible. Extremely low coolant temperature is unlikely because a properly functioning cooling system maintains a temperature around 90 degrees. I recommend not taking this lightly, as an inaccurate temperature reading may prevent overheating warnings, potentially damaging the engine. Pull over safely, open the hood, and check the sensor's location—usually near the engine cover. Try cleaning or tightening the connector. If that doesn’t help, visit a professional auto repair shop for diagnostics.

[DelGemma]

My car also has the issue where the coolant temperature always shows 0 degrees. There could be several possible reasons: a faulty coolant temperature sensor is the most common—aging instruments or excessive vibration can cause malfunctions; loose or corroded wiring connections can interrupt the current; a blown fuse in the fuse box requires replacing the corresponding labeled one; a bug in the instrument display unit might stubbornly show 0; another scenario is insufficient coolant or a faulty pump, but these wouldn’t directly cause the temperature to display 0. Remember, after a normal startup, the coolant temperature should gradually rise to a stable level. If it still shows 0 after driving for ten minutes, it’s likely a system fault. Don’t delay—you can start by checking if the sensor connector is secure, then inspect the fuse, or ask a friend to help test the circuit continuity. If you can’t resolve it, take it to a repair shop.

[SanTucker]

It's really frustrating that the water temperature stays at 0 degrees. I've tried several times, and most of the time it's because the sensor isn't working. When the engine heats up, the water temperature should display normally. If it remains at 0, it means the signal isn't reaching the dashboard. Simply put, the possible causes include a faulty sensor, broken wiring, or a blown fuse. If you notice this while driving, be careful—don't assume the engine is actually cold. It might be overheating without warning, which can damage the engine. Check it yourself after parking, but safety comes first.