D8 Remote RF Key Fob Question

[HimBigChief]

When I got my D8, the remote locking key was knackered, with the actual clicky button bit missing from the PCB inside the key. I also have the radio frequency (RF) key as stated in the title.

I have since bought another key off the Bay of E and was wondering if I would be able to reprogram this one to my car. It has a different serial number (as to be expected) but is also a primary key (the same as my original). I have already swapped the PCB and top cover over as the buttons were in better condition and just now need to program it to my car if I can. I have tried several of the old reprograming/re-synching techniques found using the search function but none of them have worked (which I am not 100% suprised about) and most search results appeared to be more D9 related.

Please tell me that I'm not going to have to go to the main stealers and fork out loads and loads of hard earned for a new key fob!

James

[teamster1975]

James, unsolder the button from your ebay key and transplant it to your existing one!

[mjb]

You have two options:
1. Do as teamy says, grab a soldering iron and switch the button over (or get a new surface-mount button from maplins to avoid any heat damage)

2. Get a new key cut and programmed by a dealer for about 150 quid

[HimBigChief]

James, unsolder the button from your ebay key and transplant it to your existing one!

Bugger, thought that might be the case. I'm not the most steady handed of persons at the best of times! However I do have a soldering iron in my workshop/shed, so I shall have a crack at doing this later on today and post an update with what happens...

Lets face it, the worst that's going to happen at the minute is that the light stops lighting up on the keyfob when I press the buttons!

[HimBigChief]

I haven't yet had time to swap the buttons over, but I now have another possibly related problem. Oh joy!

When I got the car a few weeks back, I didn't get an immobiliser code, and the immobiliser pad switched off with the key in the ignition anyway and allowed the car to start, now however it doesn't.

In the time since I last ran it (over a week ago) I have played with the fuses (putting the shunt back in the correct place), swapped batteries over again as the other one had slowly discharged over the last week and have also replaced the back box, the bottom bush in the rear o/s hub and also adjusted the handbrake on the n/s. I've also played about with keyfobs, chopping and changing bits, but as my original one never worked I can't see this being the problem, especially as the immobiliser chip is contained just above the blade (I think) and I still use this part.

Anyone got any ideas on what could have caused this? Is there a generic override code or is there some easy way to bypass the immobiliser, or am I going to have to get it de-coded somewhere? I suppose it's an excuse to get the car re-mapped at the same time as I guess they should be able to adjust all sorts of ECU parameters while they're in there.

Thanks for all the help guys!

[mjb]

Inside the key will be a little black lump of plastic (or maybe ceramic, i'm too hung over to remember). That needs to stay with the key as it's a passive RF transponder that communicates with the immobiliser via an aerial around the ignition barrel

Another way of disabling the immobiliser is - turn the ignition off, turn it back on, then press the button

[HimBigChief]

Inside the key will be a little black lump of plastic (or maybe ceramic, i'm too hung over to remember). That needs to stay with the key as it's a passive RF transponder that communicates with the immobiliser via an aerial around the ignition barrel

The little black lump is attached to the piece of the key fob which stays with the key blade, so the key and transponder are still together no matter which RF PCB I put in there. The only thing I can think is that I tried to synch the car to a different key fob (different serial number). Whether that has caused the issues or not I don't know. I have also tried the key with both the new and old PCB's in there and neither had any effect. I have also tried holding the other key near the ignition barrel while using the proper key, again no effect.

Another way of disabling the immobiliser is - turn the ignition off, turn it back on, then press the button

Also, because my key fob has never worked (no button - see above), I can't do this! I can't see any other reason for the immobiliser becoming activated other than battery disconnection, etc.

Just to clarify, I have never had a working RF key as the button for the main lock/unlock was missing from the PCB, still need to solder new one on (see above), so therefore I was doing all the locking/unlocking manually with the drivers door lock. Then when I got in the car, I used to just put the key in the ignition and the immobiliser would automatically deactivate. Now however, all works as before except that the immobiliser doesn't de-activate and I don't have the 4 digit code so therefore the car is just a pretty(ish) drive ornament at the minute! The missus isn't best chuffed!

I suppose I should try swapping the button over and then see if that fixes the problem. I'm not the best with the old soldering iron though! Bit heavy handed and club fisted!

[HimBigChief]

Quick update, still not sorted the switch on the key yet (I will get round to it promise!), but I have however got the immobiliser code from the previous owner. Unfortunately, I can now enter the code and the green light comes on, but the red light doesn't go out. Currently doing a search for red and green so will see what that turns up. Hopefully I'll get the car sorted soon and back down the MOT station.

[teamster1975]

Quick update, still not sorted the switch on the key yet (I will get round to it promise!), but I have however got the immobiliser code from the previous owner. Unfortunately, I can now enter the code and the green light comes on, but the red light doesn't go out. Currently doing a search for red and green so will see what that turns up. Hopefully I'll get the car sorted soon and back down the MOT station.

Disconnect the car battery for 5 minutes and reconnect. It seems to do that when the wrong code has been entered too many times (as I found out!)

[HimBigChief]

Tried leaving the battery disconnected for 45 mins or so, and... no joy. Still doing the exact same, so having read through a load of the search results, I shall have a good look throught the fuses tomorrow and see if I can spot any blown ones. I shall also put spares in for each of the fuse ratings as there's currently only one spare fuse I think.

Actually, think I'll pop out now and disconnect the battery and leave it disconnected for the night. See if that helps at all.

[HimBigChief]

Left the battery disconnected for over 12hours last night, reconnected and tried again, nothing. Exactly the same problem, but red and green lights on, so I pulled out and checked all the fuses in the fuse box and engine compartment, and all were fine. I then remembered that I'd kinda fiddled a bit with the wires under the steering cowling when trying to fix the first problem (live and permenant appeared to be the wrong way round), so also remembering in other posts I'd read about the key transponder pick up wire, I decided to remove the top cowling (round the indicator/wiper stalks) and couldn't see any tranponder pick up wire/ring, so moved what could have been said wire (fairly thick and black) closer to the ignition. Tried it and job's now a goodun! Car starts and runs fine, just need to get it down the garage next week, get the brakes bled and get it MOT'd. Then I need to look at the noisy tensioner, however that's for another topic in another forum.

[teamster1975]

Well done Chief! Good luck with the MOT!