Key Failure

[Aeneas]

On Saturday last the driver door-handle locking mechanism on my new Prius would not work, ie where you put your finger on the handle. Neither would the lock on the key, ie where you press the lock button on the key itself. When I tried to start the car I got a screen message telling me i) that the key could not be detected and ii) that I should press the key against the power button. Nothing happened. I had to call my wife to pick me up with the second key which worked. Luckily I was only about fifteen miles from home. My own key seems to be working again now (Monday) but I am concerned that it is unreliable and that I will be stranded again - this time at an inconvenient distance. Any suggestions why this might have happened?

[THX]

Our underground company car park has something which causes interference so I usually have to open the car via the pin-like key and then touch the fob to the start button to start but this starts it every time and it is only in one spot in the parking area that I get this problem. Just in case you didn't follow the procedure fully: You have to hold the key to the power button and then physically press the Power button.

[Aeneas]

Our underground company car park has something which causes interference so I usually have to open the car via the pin-like key and then touch the fob to the start button to start but this starts it every time and it is only in one spot in the parking area that I get this problem. Just in case you didn't follow the procedure fully: You have to hold the key to the power button and then physically press the Power button.

Yep. That's what I did, but nothing happened. There was no problem with the second key, which locked and opened the door and started the car in the normal way in the same location. It looks like it was a problem with the first key. That key is working fine now (but as I say above I am afraid it will let me down again). This is what puzzled me,and why I thought I would ask if others had encountered similar problems. It may be the Battery (but the car is only a few months old), it may be that the key was subject to electrical interference earlier which temporarily disabled it; it may be that it is defective in some way.

[wizzlon]

Our underground company car park has something which causes interference so I usually have to open the car via the pin-like key and then touch the fob to the start button to start but this starts it every time and it is only in one spot in the parking area that I get this problem. Just in case you didn't follow the procedure fully: You have to hold the key to the power button and then physically press the Power button.

Yep. That's what I did, but nothing happened. There was no problem with the second key, which locked and opened the door and started the car in the normal way in the same location. It looks like it was a problem with the first key. That key is working fine now (but as I say above I am afraid it will let me down again). This is what puzzled me,and why I thought I would ask if others had encountered similar problems. It may be the Battery (but the car is only a few months old), it may be that the key was subject to electrical interference earlier which temporarily disabled it; it may be that it is defective in some way.

In the cold outdoors the other day, I started and drove a few yards. I then got out to open a gate. On getting back in, the car displayed the message key not detected. I shut off power and switched on again, all was well. I have also had problems with the "touch" locking- won't open or lock. I wondered if it is dirt on the handle- as the whole car is coated in crud off the road at this time of year.

[kithmo]

I wouldn't think dirt on the handle would affect the smart entry/exit system, I've operated mine ok with thick woolly gloves on this last 2 days.

[DrCez]

Any suggestions why this might have happened?

As others have said, assuming the key is working normally the most common problem is electromagnetic interference but this doesn't seems to fit what you experienced.

I had an intermittent problem with one key on my previous car, a Renault Megane, which used an electronic key (a bit like a fat credit card that slid into a slot on the dash). After a could of years of trouble-free use the car started to occasionally fail to detect the key (& so wouldn't start). Changing the Battery didn't help and my emergency solution was to tap or shake the key but it got progressively worse until it stopped working altogether. The second key continued to work so I carried it as a backup. I think maybe something worked loose and eventually broke in the first key (it did get dropped a couple of times which can't have helped!). It was pretty expensive to replace the key (over £100 I seem to remember), so if yours is faulty I hope it is covered by a warranty. If I were you I would carry both keys over the next few months in case the problem re-appears.

I haven't had any problems with my Prius except one possible instance when touching the handle failed to unlock doors, and I put that down to localised electrical interference.

[Aeneas]

I haven't had any subsequent problems. And the car locks even with thick woolly gloves! But I shall probably take the second key with me on long journeys just in case.