Hi All Can anyone tell me if it is possible to disable or reset or temporarily turn of the immobiliser on a K Plate diesel discovery. The immobiliser won't disengage and I have been told that the 4 digit code on the grey tag that came with the keys is some sort of override facility that you can use to temporarily turn of the alarm and immobiliser system. I've been told that turning the key to lock and unlock the driver's door following the code on the tag is the way to do it, however, this has not worked. If this is correct is there a set sequence of operations to follow? There is nothing in the handbook about this. It has a single button transmitter and that still be sets the alarm and operates the central locking however the immobiliser won't disengage. The electric windows also are not working. I've checked all the usual things I can think of and now I'm totally stuck. I would be extremely grateful for any help, advice or suggestions as the only option it seems at the moment is to have it towed into a Landrover dealer!!
What makes you think the immobiliser isn't disengaging ? I ask this as the immobiliser "spider" is notorious for failing by leaving one or more circuits disabled. If this is the case then, as a temporary fix, you can simply bypass the relevant circuit. I haven't looked at the circuit diagrams but my guess would be that the fuel pump and the starter are controlled by the spider and possibly the heater circuit ? If only one of the circuits is effected then the immobiliser spider is faulty or you have a wiring problem on that circuit.
My 300Tdi handbook has a complete sequence for this, which I could copy and post if you like .. But mine is a '97 version with a two button 'plip' .. Post back if you want me to do it .. ;)
Hi Dave I'm afraid I have no idea what/where this "spider" is...there is power to the heater plugs and they are working correctly.....the fuel lift pump is mechanical so I'm not sure what you mean when you say the pump is controlled by this spider...if you mean the fuel shut off solenoid for the injector pump then that is working ok too...the reason i think the immobiliser is not disengaging is that there is no power to the starter solenoid......the main battery feed to the starter is ok and i've tested the starter off the car and that is working fine too..if you can describe or tell me what/where this spider is i can try checking that out....
If it is not too much trouble i would be grateful if you could do this if you have the time...admittedly the car is an earlier model than yours with the single button transmitter so it may not work the same way but at the moment tearing my hair out and prepared to try anything!
No worries .. Directly copied from the handbook ..
-------------------------------------------------- Engine Immobilisation Override (entering the emergency key access code)
If the handset is lost or fails to operate, the engine can be re-immobilised by using the key to enter a unique four digit emergency code. The code is recorded on the Security Information card and is entered as follows.
Using the key, turn the driver's door lock (clockwise) to the LOCK position and hold in this position for at least five seconds. Then return the key to the centre position. It is now possible to use the key to enter the separate numerical values of the four digits that make up the emergency key access code.
Enter the FIRST digit of the code. If the first digit is 4, turn the key (anti-clockwise) to the UNLOCK position 4 times. Ensure the key is FULLY returned to the centre position each turn of the key.
Enter the SECOND digit of the code. If the second digit is 3, turn the key to the LOCK position 3 times. Remember the key must be FULLY returned to the centre position after each turn of the key.
Enter the THIRD digit of the code. If the third digit of the code is 2, turn the key to the UNLOCK position twice, ensuring that the key is FULLY returned to the centre position after each turn of the key.
Enter the FOURTH digit of the code. If the fourth digit is 1, turn the key to the LOCK position once. Ensure the key is FULLY returned to the centre position after the key has been turned.
FINALLY, turn the key to the UNLOCK position once more to disarm the alarm and re-mobilise the engine. If the code has been entered successfully, the anti-theft alarm indicator light on the instrument panel will extinguish and the engine can be started.
If an incorrect code has been enteredthe sounder will bleep twice and the anti-theft alarm indicator light will continue to flash. In this case, return to '1.' and re-enter the code.
NOTE: Once the engine immobiliser has been deactivated by entering the emergency key access code, it will remain inactive until a handset is next used to lock the vehicle.
I tried this, just now, and it _does_ work ... including the engine immobilisation remaining inactive unless the handset is used to lock it. ie There is NO engine immobilisation when the key is used to unlock the vehicle in this manner .. ;)
OK, basically the "spider" as it is known is a black box that has a series of relays in it (amongst other things). It is used to disable a number of circuits when the immobiliser is active and therefore is also used to enable those circuits. The immobiliser can actually be functioning correctly but a fault in the spider can result in one or more circuits remaining disabled due to a faulty relay.
As a V8 man, you'll have to bear with me but I was under the impression that there are two pumps on a TDi - an electric one in the tank and a mechanical lift pump. This may not be the case, as I say I'm a V8 man !
If everything except the starter is operating then I'd suggest bypassing the spider on that circuit. The spider is located in a deliberately inaccessible place. It is behind the radio mount and can only be reached by removing the centre of the dashboard. The starter circuit can be bypassed quite easily IIRC.
If you remind me of the year and model I'll have a look at the appropriate circuit diagram and let you know how.
thanks for doing this I really appreciate it :) sadly it didn't work on the car though.....I think the alarm system was changed sometime around 94 or 95 and I guess this procedure only works on the later models.....once again thanks for your efforts though
Thanks for this I appreciate it :) it's actually a friend's car and as far as I checked or maybe I just assumed there was only the mechanical lift pump being more used to my own highly un-electrical/un-technical early 90....lol but I will check it out......and very useful knowing now where the black box is actually located...I hadn't wanted to start pulling the entire inside of the car apart just yet until I knew roughly where it was located....I've got hold of a circuit diagram but if I get stuck will take you up on your kind offer.... thanks once again
We had a problem with our Discovery a few years ago where it locked itself when it felt like it, and when it did finally let you in the immobiliser had immobilised it. We took our documents in to the local land rover dealer to prove that we actually owned the car and Bruce telephoned them from where I had had to leave it. The technician gave Bruce instructions over the phone on how to bypass the alarm and immobiliser. I have asked Bruce if he can rememeber, but he said it was too long ago and he never wrote it down. Any way it worked and it started first time so a phone call may be worth the effort to either Land Rover or to the company who have fitted it, if you know who they are that is.
Depending on the age of the vehicle - pre-96 vehicles don't seem to have a spider. Having done a bit more research it seems that the earlier versions (pre-96) have the immobiliser circuit as part of the alarm rather than as a separate item.
The alarm provides an earth for the starter relay that in turn provides power to the starter motor when it is activated from the ignition switch. You need to see if the starter solenoid relay is activating - it's behind the RH footwell trim panel (the one at the side). If it isn't then try earthing pin 86 of the relay to bypass the alarm immobiliser. If it is operating then you have a problem with either the supply to the relay or the wiring from the relay to the starter solenoid.
thanks Dave and to everyone else for the help with this.....:)) finally tracked it down to damaged/corroded wiring loom and connectors behind centre console and dash panel.....i think it was shorting out.......fixed/replaced bad sections and all seems to be working again now...touch wood!!....lol
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