There are a couple of alarm bells being set off here. The first is that the engine, if driven through water deep enough, may have ingested some of that water which has caused what’s called hydraulic-lock. This is usually terminal and involves the (non-compressible) water, bending or breaking the engine’s internal bits and pieces such as the crankshaft and connecting rods. If the engine won’t turn over at all, this could be why.

The second possibility is a little less scary and involves the flood-waters entering a part of the car’s electronic or ignition systems, leading to a short-circuit. If that’s the case, the parts can sometimes be dried out and the engine will restart. In modern cars, however, once the computers and other electronics have been wet, they corrode internally and will need to be replaced over time.

This is part of the reason that insurance companies tend to write off flood-damaged cars, even if there’s no other damage. Insurers know that a car that has been under water will come back to haunt them in the longer term as all sorts of electronically-controlled components go belly up.

A common cause of this fault is failure of what’s known as the clock-spring which lives inside the steering column. But it’s not a spring at all, it’s actually the electrical connector that joins the air-bag (and steering wheel controls if your car has them) to the rest of the car’s electrical systems. It’s called a clock-spring because it’s wound in a spiral shape to allow the steering wheel to turn from lock to lock without the connecting wiring binding or bunching up. Eventually, fatigue gets the better of a clock-spring and it snaps, allowing the connection to fail. And that’s very probably what’s causing the air-bag light on your dashboard.

But don’t ignore it, as the clock-spring is also responsible for sending the correct signal to the air-bag in the case of a crash where the bag needs to deploy. And driving with an air-bag that may not go off when it should is a terrible idea.

Yes, it is.