Can drive — fix at your convenience.
This code means the engine coolant isn't reaching the temperature the computer expects for stable, efficient operation, often because the engine is running cooler than it should. The most common cause is a thermostat stuck open, but a faulty coolant temperature sensor or cooling system issue can also trigger it. It's usually an inexpensive, straightforward repair, most often a thermostat replacement.
$150 – $450
Varies by vehicle and root cause.
Yes, in most cases it's safe to keep driving. The engine just runs cooler than ideal, which affects efficiency more than safety, but it's still worth fixing to avoid wasting fuel.
Usually $150 to $450. A thermostat replacement is the most common fix and is fairly affordable, while a coolant temperature sensor or wiring repair may cost a bit more.
It's low severity. It won't typically damage the engine in the short term, but running cool long-term hurts fuel economy and emissions, so it's best to repair it before your next inspection.
A thermostat stuck open lets coolant flow constantly, so the engine never warms up enough to reach its target temperature. The computer notices the coolant stays too cool and sets the code.