Key fob got wet: the first things to do
Water on its own seldom ruins a fob. The harm comes from electricity: a battery pushing current across damp contacts causes short circuits and speeds up corrosion. Cut the power, give the water time to leave, and many fobs recover.
- Get the battery out. Most fobs split along a seam with a thumbnail or a coin in a small notch. On many smart keys you slide out the hidden blade first, and the case opens from that slot.
- Open the case only if it is designed to open. Prying at a sealed shell cracks it and lets in more water next time.
- Shake out and blot. Tip out loose water, then dab the board and battery contacts with a lint-free cloth or cotton swab.
- Dry it at room temperature. Leave the pieces open on a towel in a dry room with some air moving. Allow a full day, and longer if it was soaked.
- Keep heat away. A hair dryer, oven, heater vent or sunny dashboard can warp the plastic and loosen parts on the board.
Skip the bowl of rice as well. Rice pulls out no more water than open air does, and its dust can work into the buttons. A closed container with a few silica gel packets is a better choice.
Why some water is worse than other water
Rain or a puddle is mostly clean water. It dries without leaving much behind, which is why a fob caught in a downpour often works again once it is dry.
Lake water is another matter. A fob that goes into Lake Lowell or the Snake River comes out carrying minerals and grit that stay on the board after the water is gone. Winter slush off treated roads is harder still, because salt keeps conducting electricity and eating at metal contacts. With either one, act soon instead of waiting to see whether it still works.
A trip through the washing machine adds detergent and a long soak. If the fob then rode through the dryer, the heat may have warped the case or damaged the battery, so look for a swollen or leaking cell.
The three parts of a key, after a soak
A car key can have three working parts, and water treats each one differently. The blade is solid metal and only needs drying. The remote, the part that locks and unlocks from a distance, carries a battery and a small circuit board, and it is the part most likely to fail.
The chip is what tells the car the key belongs to it so the engine may start. It is a transponder: a tiny sealed radio part with no battery, powered by the car itself each time you start. Because it is sealed and draws nothing from the fob's battery, the chip often survives a soak even when the remote buttons have gone dead.
That is why a wet remote-head key or flip key may still start the car while the lock buttons do nothing. With a push-to-start smart key, the car may still read the chip at its backup spot, often the start button, when you hold the fob against it.
Getting into the car while the fob is dead
Most smart keys carry a small metal emergency blade tucked inside the fob for this exact moment. It slides out when you press a release on the case. The driver's door lock is often hidden behind a small cover on the handle, and the owner's manual shows where to find yours.
Opening the door with a blade can set off the alarm on some cars, since the car expected the remote. Starting the engine with a recognized key usually quiets it.
After it dries: testing, and what to do if it stays dead
Put in a fresh battery rather than the one that got wet; the type is printed on the old cell. Try lock and unlock beside the car, then from farther away, then try starting it. Short range or one dead button usually means corrosion has started on the board.
If the remote stays dead, it needs replacing. A new fob or smart key has to be programmed to your car before it works, and we do that at the vehicle: see replacement key fob programming, or smart key replacement for push-button cars. The service vehicle comes to wherever the car sits, in Nampa or anywhere else in Canyon and Ada counties, including Caldwell and Meridian, 24/7. Call (208) 480-6980; the price is explained on that call, before anyone drives out.
Thinking about ordering a fob online instead? Call first so we can check it against your car. Many fobs sold online can't be programmed to the vehicle, so nothing is promised for a fob that came from somewhere else.
If the wet fob was your only one, this is also a good time to have a spare key made.