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Q: Low coolant level warning

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The dashboard in my car shows the "low coolant level" warning. It occurs only on the startup. However, I keep the coolant at the optimum level at all times. Why is this warning coming up?

A: Hello. If the coolant level shows low when ...

Hello. If the coolant level shows low when the coolant is cold, and then reads fine once it warms up, then most of the time this is due to a bad coolant level sensor. This is assuming that the coolant is indeed at the correct level.

If it is, then I usually start by testing the sensor itself to see if it is reading correctly. Most of the time this is the problem. In some cases it can be a wiring issue, but that is not as common. If you are going to have this repaired, consider YourMechanic, as a certified mechanic can come to you home or office to diagnose your coolant warning light and repair this.

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