Thread: Is there any 'intelligence' (like a chip) in a PUMA key? Won't start with Spare Key.

The keys supplied from LR are just that, keys. The key fob, plip, has the necessary electronics installed to allow the mobilisation of the Puma. So if the AS10 is working fully and nothing has been disabled then you will need to have a key Fob in close proximity to the ignition barrel to allow the transmission of the mobilization code to allow the Puma to run. If this fob is not present then the AS10 will not send the mobilization signal to the EMS and the engine will shut down.



The passive immobiliser works by switching on the immobiliser after a set time once the key/fob is removed. It detects this by using the transceiver coil on the ignition barrel to detect the key/fob. If there is a problem with the passive immobiliser through a fault with the transceiver coil or fob then it will act as if the key is removed by initiating the immobiliser which will stop the engine by inhibiting the starter and fuel injector circuits. The pulsed feed from the 10AS module causes the magnetic field created by the transceiver coil to collapse and restore. The fluctuating magnetic field activates the fob (remote RF handset) to transmit a mobilization code to the 10AS module. The 10AS module receives the fob mobilization code via its antenna. This fob code is compared to a value in the 10AS memory. If the codes match, the 10AS module provides a mobilization signal to the instrument cluster. The instrument cluster acts as a gateway, converting the signal transmitted from the 10AS module into a signal that is recognizable by the ECM (AS10 Serial to Multiplex between the IC and EMS).

Another reason for spare Fobs not working as they should is that they have lost synch with the AS10 unit. The standard value within the AS10 for resynch is set to the value Two. Basically lock and unlock the Puma 2 times with the fob buttons. This will allow a basic resynch of the fob and AS10 unit. If this doesn't work try the it 4 times as this is a full resynch. What has been described by other members in combating a non start issue is basically a resynch by locking and unlocking the car a couple of times to get it to run. If that doesn't help and you have a diagnostic tool like the nanocom or MSV then just do a plip relearn of ALL fobs as this will resynch everything. There are other parameters which can affect the fob working like bad plip keycode allowance and the fobs battery being low.



HTH Brian.

Originally Posted by spudboy

Frank - I have a Nanocom for my TD5 (one of the original 'old style' Nanocoms). Any chance it will plug into a PUMA, or is this only for the updated 'Windows style/graphical' Nanocom?

Be good if I could switch off the immobiliser for the trip and then turn it on again when we get back.

No, it will not work as the TD5 and Puma use different protocols and the OBD plug is wired differently for the TD5 and Puma.