Drivable short-term, but fix now to avoid damage.
This code means the engine computer detected a problem in the electrical circuit for ignition coil H, which fires the spark plug on one of the cylinders. It usually points to a failing ignition coil, a damaged wire or connector, or a problem in the coil's wiring harness. It's a common code and is often fixable by replacing the affected coil and repairing any damaged wiring.
$100 – $350
Varies by vehicle and root cause.
For short trips, usually yes, but you shouldn't rely on it. A failing coil causes a misfire that can overheat and damage your catalytic converter, which is far more expensive to replace. If the light is flashing or the engine shakes badly, stop driving and get it towed.
Most repairs run between $100 and $350, depending on your vehicle. A single ignition coil is fairly inexpensive, and labor is usually quick. Costs go up if wiring or connectors also need repair or if multiple coils are replaced together.
It can be. While a single misfiring cylinder won't strand you immediately, ignoring it risks catalytic converter damage and rough running. It's best to treat it as a soon-to-fix repair rather than waiting.
The letter is just a label your vehicle uses to identify which specific ignition coil is having a problem. A technician uses your car's wiring diagram to match coil H to the exact cylinder so they can replace the right part.