In the UAE, a persistent green light on your Nissan's temperature gauge primarily indicates the engine coolant is below optimal operating temperature, most commonly due to a thermostat stuck in the open position. While less common in the UAE's hot climate compared to cold regions, it still occurs, especially in vehicles like the Nissan Patrol or X-Trail with aging cooling systems. A faulty thermostat (often costing 300-500 AED for the part) continuously circulates coolant, preventing the engine from reaching its efficient 90-95°C range. This leads to poor fuel economy—you might see a drop from 8.5 km/l to around 7.8 km/l on a Patrol in mixed Dubai-Sharjah traffic—and increased engine wear over time. The RTA Dubai vehicle inspection manual notes that improper engine operating temperature can affect emissions readings. For accurate diagnosis, a mechanic would first check the thermostat and then the coolant temperature sensor, a common point of failure in dusty conditions. Ignoring this can increase fuel costs by 5-10% annually and is an advisement point during vehicle testing at authorized centers like those enforcing MOI UAE standards.
- Optimum operating temperature: 90-95°C
- Common faulty part: Thermostat
- Typical part cost range: 300-500 AED
- Impact on fuel economy: Can decrease by 0.5-0.7 km/l
