What is the reason for the Nissan water temperature gauge always showing a green light?
2 Answers
Nissan water temperature gauge always showing a green light indicates that the water temperature is too low. The following are the specific reasons for the low temperature of the water temperature gauge: 1. Thermostat failure: The thermostat is always in the large circulation position. After starting the car when it is cold, the engine is in large circulation, resulting in too low water temperature and the engine cannot warm up. 2. Water temperature sensor failure: The water temperature sensor fails, leading to the recognition of incorrect water temperature. At this time, the water temperature may not be the actual water temperature of the engine. 3. Abnormal electric fan: It is not controlled by the engine and is in a constant rotation state, causing the engine water temperature to never rise. 4. Large temperature difference between the engine and the external temperature: If the weather is extremely cold, the water temperature will rise slowly. It is recommended to warm up the car for 2 minutes before driving until the temperature rises.
With over a decade of experience in driving and car repairs, I've encountered various common coolant temperature issues in Nissan vehicles. A persistent green light on the coolant temperature gauge indicates that the coolant temperature is too low or stuck in a cold state. The most frequent cause is a thermostat stuck in the open position, which allows excessive coolant circulation and prevents the engine from reaching optimal temperature. It could also be due to a faulty coolant temperature sensor, wiring short circuits, or insufficient coolant triggering false signals. Don't ignore this issue—prolonged engine operation at low temperatures increases fuel consumption and mechanical wear, especially noticeable during winter startups. I recommend performing a simple self-check: start the engine and wait 5 minutes, then feel if the upper radiator hose is warm. If it's not warm, it's likely a thermostat issue. Afterwards, take the car to a professional shop for a diagnostic scan to avoid minor issues escalating into major repairs. DIY part replacements may not fully resolve the problem, so professional repairs are more reliable.
