Is there a correct tool for removing the back of the keyfob? I'm totally unable to remove it without knackering the slot which means I need to buy a new one each time for fear of being left with something that will be stuck forever.

Also, I've been getting intermittent Key Battery Low warnings recently, and now the damn thing won't work at all. No red light, nothing. I finally got the back off and tested the batteries at... 6.02V. Gah.

The contacts look to be springy and in the right place, is there another fault that could cause this? (I suspect there will be several options).

Time to bend over for the Landrover dealer and shower him in money for a second fob :(

The solder holding the two contacts can crack so you get a dry joint. Hardest part is getting the two halves of the fob apart. I also got the Key Battery Low warning last week, so decided I'd put some new batteries in it. Got the back off with a 50p piece (but I have been known to drill two small holes in the back so I can use the points of a pair of needle nosed pliers to undo it), changed the batteries and it didn't work. No red light, no nothing. After mucking about with it for about an hour (including putting the old batteries back and finding it still didn't work) I decided that the solder had cracked from me messing around with it. The only way I could get the fob apart (original LR one not an eBay special) was to wedge a Stanley knife blade in the seam and then put the blade and fob in a vice. With a bit of careful squeezing, the fob popped open on the one side. Had to do both sides and one end before I could get it apart though. Re-soldered the contacts even though they looked perfectly OK, tried the battery on the pcb out of the case and still nothing. Then looked at it again and realised I'd been trying it with the batteries in upside down. The big + on the bottom of the battery holder, isn't there for decoration.........

Thanks Richard. I guess it's time to break out the soldering iron. Until then I'll just have to leave the nanocom plugged in :/
FFS.

I've seen Marty replying to someone where he states that the the small lip that goes along both batteries might contact both, resulting in only 3 volts. He says put a small strip of insulating tape on the battery where the lip passes to avoid this.

Ferryman, I did wonder if there was something odd going on like that so I tested the two batteries in the back/holder and got 6V. The back is incredibly hard to turn in the fob though :(

Trouble is, I can't start the thing without the fob working. I can enter the EKA via nanocom but it just won't start. Last night it started after about 5 attempts (maybe a fluke connection from the battery) but this mornng without batteries working in the fob - nothing. Just "Engine Disabled, Press Remote"

Can you start it if you enter the EKA through the door lock?

tbh I haven't tried that. I assumed (!) that the nanocom would be eqivalent to the door lock method. I'll give it a go tonight - I'm hoping I'm not in danger of getting into some extra-locked-out mode if I keep trying.
I've ordered a new back and batteries so I'll give that a go as well but I suspect I'll be buying a new fob very soon (payday tomorrow!) and then hacking the existing one to bits looking for bad connections.

Once you've got the EKA entered so it will start, then you should be able to lock and unlock with the key. If locked with the fob but unlocked with the key then the immobiliser is still on, however, if you lock with the key, you can unlock with the key and the immobiliser should be turned off. If you use the Nano to turn off Immobilisation then you won't get the press remote or enter code message if you don't start it immediately. My SE is set like this as I've only managed to get the fob to work for about 10 minutes before it has died again. When I bought it, I was given the key blade to use and the fob was separate and had never been used by the previous owner.

Hmm, I smell problems.
I can lock/unlock with the key (All doors) but the engine is still disabled, even after unlocking with the Nanocom.
Bollox.
edit: I guess the next step is to enter the EKA and then disable the immobiliser using nanocom?

Yes, it might be the 'passive immobilsation' playing up Morat [RFID-type coil around the ignition switch, chip/tiny coil in the fob - and which can go out of sync (or just fail)] and so turning off the immobilisation would definitely help. Interesting that it started then stopped like that though so this passive part may be intermittent... but it might be the ignition (RF) coil connection to the BECM (?)

"B%%%%D Keyfobs" is right, Once that slot is knarled it is 'game over' and so like Gilbertd above I carefully drilled some holes - and made a 'special tool' (just two little bolts in some ally strip to get some traction/torque..) Yes, "B%%%%D Keyfobs" for sure (sorry but I do feel better now..)

If the central locking is working on all doors, then it shouldn't be needing the EKA... do you actually still get the 'engine disabled' message?

Sloth wrote:

If the central locking is working on all doors, then it shouldn't be needing the EKA... do you actually still get the 'engine disabled' message?

• Think this might be some confusion between "Key Code Lockout" and "Engine Disabled" Sloth (?)
  (ie. you can get into the car OK but it still won't let you start it... and you need EKA to remove the former)

I'll check the exact messages again when I get home, but I'm still definitely unable to start it.
Oh, and the alarm doesn't do the little squawk when I open the door on the key like it does if you open the door with the key after locking with the fob.

davew wrote:

Sloth wrote:

If the central locking is working on all doors, then it shouldn't be needing the EKA... do you actually still get the 'engine disabled' message?

• Think this might be some confusion between "Key Code Lockout" and "Engine Disabled" Sloth (?)
  (ie. you can get into the car OK but it still won't let you start it... and you need EKA to remove the former)

Key code lockout prevents you entering the EKA. If all the central locking is working on all doors, then, so far as I am aware, the EKA should not be required and the engine should start.

Unless of course the BECM and engine ECU have lost sync. Then, in the case of a Thor/Bosch, it will happily crank all day and not start. It won't display any 'Engine disabled' message either. Though if it is still displaying that, then... weird.

Yes, I did not mean and you need EKA to remove the former but "you can only enter EKA once the former is removed"

Still don't understand what is happening here either unless it is something (physically) intermittent though...
(or the system was already 'got at' somehow ?)

The only possibility I can see is that because the fob has no batteries in it, the passive immobiliser isn't getting any signal from the fob at all and that is preventing the car from cranking. BUT I don't know if that is possible on a P38, I'm going with experience from a BMW.

Ah, no that's the point, being passive the fob does not need batteries for this to work (like a contact-less card);
I am not sure if this is OK to do, but here's the link: http://www.rangerovers.net/repairdetails/becm/alarm.html

davew wrote:

Yes, I did not mean and you need EKA to remove the former but "you can only enter EKA once the former is removed"

Still don't understand what is happening here either unless it is something (physically) intermittent though...
(or the system was already 'got at' somehow ?)

Ahh :) I get you.

Might need to recap what its currently doing - messages, locking etc. It should be possible to start the car with a fob with no/dead batteries, that's the point in the EKA, so something must be amiss somewhere.

Edit - Dave beat me to it!

Though I'll add - the P38 system isn't like other cars in terms of the inductive coil around the ignition barrel. On a P38 this coil tells the key to transmit as if you'd pressed a button. So the key does need working batteries and the RF receiver in the car needs to work. So if the key isn't working for whatever reason, the car won't receive the code and won't start - leaving you with the EKA.

If you disable the 'passive immobiliser' through a Nanocom etc, what actually gets disabled is the re-immobilising of the engine 60 seconds after stopping it, unless you lock the vehicle with the key, which does immobilise it. Unlocking then re-mobilises it again, assuming the door latch switches work properly.

On other cars, the key has a standalone pickup and chip in it that is powered by the inductive coil and transmits back the immobiliser code. Generally very reliable. How I wish the P38 had such a system.

Oh Marty, Marty. Wherefore art though Marty?!
What a pain in the @rse Morat...

Sloth:

Though I'll add - the P38 system isn't like other cars in terms of the inductive coil around the ignition barrel. On a P38 this coil tells the key to transmit as if you'd pressed a button. So the key does need working batteries and the RF receiver in the car needs to work.

• I didn't know that, I had the impression that coil around the ignition provided the power to the fob (as on other makes as you said later) !
  Obviously by 'passive' LR meant 'it does it by itself'' then ?! Sorry, Morat !

Ok, I don't know if this is allowed either:-

http://workshop-manuals.com/landrover/p38/86_electrical/description_and_operation/page_1502/