[dgupta]

Originally Posted by thoma

Additionally, there is a copper (I guess) coil winding going through the periphery of the fob.

This coil enables you to start the car using induction when you touch the start stop button using your key. The start/stop button houses the other half of the induction loop, when you touch the button using the fob, a loop is closed and enough energy is generated in the fob to transmit its codes.

Almost all manufacturers use either "induction charging" or a "hidden slot to insert key" to bail the driver out of a flat battery situation. Anyone has come across a different technology used for this ?

[Prowler]

Originally Posted by thoma

Correction. There is a workaround for this.

2) Though the intelligent key is termed water resistant, it is mentioned that wetting may damage the key! Do not bend, drop or strike the key against another object. Do not use a magnet holder.

3) The key may not properly work below temperature of -10 degree C. Do not place the key for extended time where temperature exceed 60 degree C (I guess we should read that do not leave the key on the dash).

Additionally, there is a copper (I guess) coil winding going through the periphery of the fob.

Magnet doesn't affect the key fob. Water surely can mess up the internal electronics. I once dropped my keys in a puddle of water. The red light did not light up when I pressed any key. I had to change the battery and clean the inner PCB with alcohol to get it working.

Here is a page about Car security in key fobs

[thoma]

Originally Posted by Prowler

Magnet doesn't affect the key fob.

Didn't go through the link provided, but from my school days, I remember that an external magnet indeed affect an induction coil. We are talking about the intelligent key fob for a vehicle is equipped with Start-Stop button; not the usual remote key fob for which I've never seen a coil inside it.

Moreover, my suggestions are a straight lift from the Nissan owner's manual.

Originally Posted by dgupta

This coil enables you to start the car using induction when you touch the start stop button using your key.

[amolbh]

In cars with a keyless start/stop button, the engine cranks only when the button is pressed with the clutch disengaged. Without pressing the clutch pedal, only the accessories would be powered. Now what if the switch gets stuck and the car thinks that the engine is to be cranked, whereas the user just wants the radio? That would mean the car would start in gear!

What kind of mechanism is incorporated to prevent this from happening?

This question arises after reading the thread: Hyundai Santa Fe recall: For replacing the stop lamp switch

[GTO]

Originally Posted by amolbh

Now what if the switch gets stuck and the car thinks that the engine is to be cranked, whereas the user just wants the radio? That would mean the car would start in gear!

Not really. Even if the switch gets stuck, you need to press either the clutch or the brake pedal (depending from car to car) for the engine to crank.

I don't know of any OEM keyless go that cranks the engine without clutch / brake pedal input.

[amolbh]

Originally Posted by GTO

Not really. Even if the switch gets stuck, you need to press either the clutch or the brake pedal (depending from car to car) for the engine to crank.

No sir, I mean what if the switch/sensor which monitors whether the clutch pedal is depressed or not, gets stuck. Like this scenario:

A defective stop lamp switch could result in the brake lamps not illuminating at all, cruise control not cancelling out and the AT gear lever being stuck in "P". I'm assuming that it basically doesn't recognise that the brake pedal has been pressed

[fazonater1911]

Originally Posted by dgupta

I can speak for LandRovers and Jags

If proper action is taken and both fobs are used periodically, above situations can be avoided completely.

Do both the fobs have to be used alternatively and periodically to prevent battery discharge?

[dgupta]

Using both key fobs will not prevent their batteries from losing charge. When a key fob is used, the system checks the battery charge state and notifies the driver if it is low.

[fazonater1911]

Originally Posted by dgupta

Using both key fobs will not prevent their batteries from losing charge. When a key fob is used, the system checks the battery charge state and notifies the driver if it is low.

I am not sure if my Grand i10 has a low battery in Keyfob indicator. Is there any way to check?

[aboveallkaran]

The best remedy to this, which even i follow is to keep a spare battery in the car. In case the one installed in key fob goes dead, you can replace it instantaneously.

[Turbo_Torq]

Apologies for bumping this thread but in the event that the Start/Stop button malfunctions or totally dies out, are there any alternatives to start the engine without having the security system arm itself and immobilise the car?

[k2max6]

I have a 2014 Verna SX O. When i reach the car and try to open the car with door entry switch the car doesn't open. If i use the remote ,same case. After a minute or two the car opens and the key also works. I guess the car takes some time to detect the key?
After the car opens once after that everything works normallly and i can lock and unlock the car a number of times or use the door switch. Doesnt seem like a battery issue does it?
How long does the smart key fob battery last generally ?
My car is not used much and keeps parked for 7-10 days and after this period the first time i use it the above happens,does it have something to do with this.

I havent tried the other key,will do so.

Edit- Also the led on the key fob is not working.

[k2max6]

Update - After an hour i went to the parking to check the key fob aand it is unlocking the car from decent distance.Without any delays.

[MSA]

Wanted to share my experience. I have a W-10 XUV with the start=stop button and a couple of weeks ago, the key didn't work on two trys but it did on third and naturally, I started panicking. After going through this thread, opened the manual and thought I'd share what the XUV manual said.

Interestingly, the XUV manual makes a mention of a weak signal strength or a weak light indicator as a sign that the battery needs to be replaced. The dealer during servicing also confirmed that there is no indicator for a weak battery and it's only based on user experience.

While I'm sure most users are careful, for the benefit of those would like to read a bit - the link to the XUV manual is here:

http://www.mahindraxuv500.com/pdf/owners_manual.pdf


Section 7.5 at page 87 onwards will be helpful - useful tips including replacing battery.

However, while the manual talks of a green light, i have never notice a green light.

One useful suggestion from Mahindra Dealer was - at 2 - 3 years you should not have any problem at all. IF at all you want to do something, consider keeping a spare battery.

A very simple suggestion but something I considered. So I went to buy a spare battery - but the accessories store in South Delhi didn't have it - and said - 2 - 3 years, you don't need a spare!

A combination of a well-maintained key and possibly smart tactics of a spare battery should hopefully see you do fine!

MSA

[torque.steer]

In my Baleno Alpha even if there is no battery in the fob, you can simply put to key fob on the start stop button and press it to start the vehicle.