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My key fob has failed and fell to bits. it will now not start the car. has the chip in the key failed or is it on the car side of things ? i have tryed shorting the starter motor out , but still wont fire. put ignition on, get lights , go to start get nothing. if i get a new key will this sort it ? i understand i will have to get it on a t4 to get the remote to work ... i have now had to dig the landrover out the garage and use that, as i only have one key . many thanks

If it's fell to bits on the literal sense then it's possible you've lost the immobiliser chip out of the fob. Without this the car will not start, even by shorting the starter motor.

There are some pictures afloat that show the inside of the fob - including the chip - in detail, but I'm currently on my phone and unable to do thorough Internet searches. However, it was not a normal rectangle shape, without any connecting wires so could easily be mistaken for something unassuming and unimportant.

The remote part and the immobilser are different things. Inside the remote is a little black chip. That's the transponder for the immobilser. If it drops out of the casing the immobiliser won't work as Simon said.

Here's a photo:


Saying that, there are many other possibilities for 'not starting'.

I assume you mean that the engine doesn't turn over. Can you confirm that? Or does it turn over but not fire?

Do you get any warning in the instrument pack of a problem with the immobiliser? On mine if the chip is wrong I get a symbol pop up saying something like engine immobiliser.

When you say you 'shorted out' the starter motor, what did you do? Did you apply 12v directly to the terminal that has the white / red wire? If yes, what happened? did it turn over but not start, or did it still not turn over?

The chip is in the key, not lost. when you turn the key to start it, it just does nothing ? you get ignition lights, then go to start and nothing ....... i thought it would turn over but fail to fire if it was anything to do with the chip ? shorted starter motor out , engine flys over but will not fire. everything was fine untill key fell to bits. will it be on the igntion side of things ? is it not reading the chip in the key.?

If the immobiliser cannot read the chip, it won't crank the engine over, either.

The chip as you can see is separate from the rest of the fob, so it's falling to bit's shouldn't make any difference, so long as it is in the right place when you switch on the ignition.

I assume that when you 'shorted out' the starter motor, you had remembered to switch the ignition on to position 2, before putting power onto the starter?

Do you get any warning in the instrument pack that the engine is immobilised (or a symbol)?

If it isn't reading the chip, there could be any number of reasons. Could be a feed to the immobiliser with a duff fuse for example. Really needs some diagnostics on it to see what the immobiliser is saying, if all fuses are OK. It might be worth checking the immobiliser unit itself, as I have seen one that had suffered from water getting in.

If it's an automatic, maybe there could be a faulty switch at the gear lever? Except in P or N the engine won't start either, so it could get a wrong signal from there.

Jürgen wrote:If it's an automatic, maybe there could be a faulty switch at the gear lever? Except in P or N the engine won't start either, so it could get a wrong signal from there.

The engine won't crank unless in P or N, but I'm pretty sure it doesn't disable starting if you bypass that.

Edit: the workshop manual says it does prevent fuelling as well, so I stand corrected, sorry.

Stupid question - is the battery flat? Classic flat-battery is non-starting and flashing/clicking of dashboard lights. The key falling apart could be a red-herring if this is the case.

sorted..... the problem was , as the key had come away form the fob , the chip has to be within an inch of the ignition barrel ,any further away and it will not start. i had the fob just a tad to far away and no go .... these things are set to try us. i will now get a new key cut and swap my chip over.

Glad you got it sorted.

Both my keys are falling apart, both rubber switches on each key are now missing so I now have to use the key in the door to unlock and lock (so no luxury of remote locking) till I get a new key.

Even one of the small switches have come of the circuit board, so need a new one of them as well.

I see many of these keys on ebay for around £15.00 new with a uncut blade (just pop in your circuit board), where do you get the blades cut and is it expensive ?

went into my local locksmiths , said it would be around £7.50 .

1gp wrote:sorted..... the problem was , as the key had come away form the fob , the chip has to be within an inch of the ignition barrel ,any further away and it will not start. i had the fob just a tad to far away and no go .... these things are set to try us. i will now get a new key cut and swap my chip over.

Sorry, perhaps I needed to be more specific:

I said the chip has to be in the right place or it won't work. That does mean within an inch of the key barrel, where it is when the key is fully assembled.

I'm surprised there was no immobiliser warning though. maybe you only get it on the highline message centre packs?