ASE Electrical and Electronic Systems (A6) 2025 – 400 Free Practice Questions to Pass the Exam

If all gauges are functioning properly except for the coolant temperature gauge, a faulty sending unit is a plausible reason. The sending unit, also known as the temperature sensor, is responsible for measuring the temperature of the coolant and sending that information to the gauge on the dashboard. If the sending unit is defective or has an open circuit, it will fail to provide the necessary data, resulting in the coolant temperature gauge not displaying the correct reading or not functioning at all.

In this scenario, the other components of the instrument panel, such as the instrument voltage regulator and the gauge itself, may be functioning normally. However, since the problem is localized to the coolant temperature gauge, the sending unit is the most likely culprit causing the issue.