Why does the car do this?

Sometimes happens on to me on the first try, but usually the second try is successful.

 

Are you the only driver, or is another key fob involved? Wireless key fobs use a rolling code system, where the code changes for every push. If your fob issues a code that is within a target number of previous codes, everything works as expected. If your fob gets too far out of sync, the car and fob have to resynchronize. Engineers struggled over the best way to do this, and what we came up with is multiple pushes. When a button doesn't work, the normal behavior for most people is to try it again. This action is used to force resynchronization.

Here is an example: Say your wife drives the car for a few days. Each time she uses her fob the code advances, so when you get the car back your fob issues an out of date code. If it is close, the car will use it. If not, nothing happens. What do you do? You push the fob button again, which advances your code to the next one. It's still out of date, but now the car knows it needs to resynchronize, since you have issued two good but out of date codes. The fob and car go through a little dance and all is good after that.

What causes fobs to go out of sync? Anything that advances the fob or car code without doing it for both. Two drivers can cause this, or having false triggers of your fob. Keeping your fob in your pocket with a cell phone can cause the fob to falsely respond, each time advancing its code. This wears down the battery in the fob and also wrecks the synchronization.

Of course, simple radio interference can cause your fob to not work. Sometimes this happens on military bases or other locations with strong transmitters, or having your cell phone close the the fob.

Tom

 

If you keep the fob in your pocket, try removing your foil underwear, and try again.

My guess is that the fob is not being "seen." Try standing closer to the car, or holding the fob in your hand. I'll bet it works the first time then.

 

Funny, how we push the buttons harder on the remotes when they don't seem to work. (Yeah, I've done it too.)

 

A few random actuations shouldn't desynchronize the system. It could be where you carry your fob, or it could be the battery in the fob. Try trading yours for the other fob.

Tom

 

Yep, foil shorts block the r.f.

Also, try keeping your cel phone farther away ... they've been known to block the FOB signal.

 

I cannot lock my car using the buttons on the doors when my wifes fob is in the car. Once she takes it with her, it locks fine.

Is there any chance the remote buttons react differently if there is a fob in the car as well?

I would try and remove the 'stored fob' and see if it works properly. I hardly ever use the buttons on the remote... So just a thought...

 

The car isn't supposed to lock if it detects a fob inside the cabin. It's a feature.

 

Ditto what Richard said. In fact, you should hear a long BEEEEEP if there is a fob in the car. This is the 'smart' part of the smart key.

I have noticed on occasion if I have my fob in my pocket with my PocketPC, it sometime won't recognize it as well. Ditto for downtown, where on occasion it won't recognize it. (In fact, I know of a parking lot where I was almost forced to key-open my old car with alarms a-blazing since there was so much interference it wouldn't recognize the signal... had to hold the fob right on the windshield for it to work... happened numerous times, always in the same lot, worked fine anywhere else. But I digress...)

 

Oh. My bad.

Assuming that there's no cell phone or mass of metal (coins, other keys, etc.) in your pocket or that you are holding the fob when the failure happens, I'd bet on a dying fob battery. As I recall you get access to the screw that opens the fob's battery compartment by removing the mechanical key.

 

I wonder if that is true? Obviously an SKS fob with a different code won't start/open your car, but does that mean they don't keep talking trying to sort things out? Hopefully not, but its not outside the realm of possibility. Might be worth trying taking her key out for a few days, see if it helps.

Rob

 

It's not just you. Mine does it, too. I don't have another FOB anywhere near it. It just freaks out for 10-20 seconds every once in a while right after shutdown and won't let me lock it. I thought it might have to do with that noise it makes right after it shuts off but I'm not sure. What is happening when the noise sounds?