As everyone knows for two years I have battled the unending issue of getting a key fob operational for my disco.

first I bought a recasted key; then scheduled an appointment with LR of Louisville to program it; got it there and they wouldn’t even touch it...swearing it was “used”. In reality they only wanted to sell me a new key, $295, and charge me to program it, $120....I refused.

for almost a year I searched for someone locally who had a NanoCom I could borrow...no dice. Then Brandon started renting his out. Got his NanoCom, got it hooked up...key would complete the entire procedure up to the end, and then would not “detect”.

I was sure at that point that I had a knockoff key; one with the wrong MHz or bad code...so I kept the NanoCom an extra week and bought a certified key from reliable source; got it in....would not code; same issue as above.

then I found an obscure comment in the NanoCom literature that referenced the RF Test; to determine if the RF Receiver is actually receiving....it failed.

so I overnighted a new (used) RF Receiver from a breaker in NC. You have to remove the entire headline to access the RF Receiver (if you do not have sunroofs), it sits in the middle of the Disco between front and second row seats.

the RF Receiver is plug and play; no recoding of existing WORKING keys is required.

the big issue with the RF Receiver is that they DO NOT make them anymore; verified by both LR of Louisville, and LR of Cincinnati, and Atlantic British...it is a discontinued part. So you will only be able to get one from a broken Disco.

that said....once I replaced the receiver, two screws, one plug, and hooked Brandon’s NanoCom back up, I had both keys programmed in less than 5 minutes.

they worked flawlessly...or so I thought.

here is the continuing debacle....

if I lock the Disco (with the fob) I can unlock it and lock it, over and over, as much as I like....but if I lock it (with the fob) and leave it over night; the next day when I try to unlock it....I have to use the key to unlock it, the first time. Then it will lock and unlock, over and over, with the fob....

so....what is it?

is it a safety feature?

is it a setting I missed in the NanoCom?

is it a bad BCU?

is it a semi-bad RF Receiver?

I am considering purchasing another RF Receiver and seeing if that is the issue, since it is the cheapest part to replace; but I have sent Brandon’s NanoCom back already...and I am afraid (with my luck) that by disconnecting the receiver I will end up needing to recode keys...even though I shouldn’t have to.

anyone have any real world experience advice?

doc

 

Hmm. I can't claim to know but I'm in the middle of waiting on keys to program to my truck. So been following your threads.

Is this condition repeatable 100% of the time?

Few thoughts/questions as I just read the RAVE manual on how this all works again:

1) The truck isn't somehow in "transit" mode, is it? (this is *not* my understanding of how it works however it might explain, as I find sometimes the documentation omits details)
2) When you lock with the key fob, is the alarm working properly ... ie fast blink for a period then the regular flashing to indicate armed status?

Page 1335 of RAVE (alarm section) says this:

"Input/Output - The BCU supplies the receiver with a 12 volts power supply. On receiving a valid signal from the handset, the receiver transmits a 1000 baud signal to the BCU to allow locking/unlocking of the vehicle. TestBook provides the ability to monitor the real time state of the remote receiver."

So perhaps the RF receiver is somehow failing to transmit this "1000 baud signal to BCU" to allow locking/unlocking" or the BCU is failing to power the RF receiver in the first place.

A good mystery, for sure.



Maybe you do have a bad new RF unit? Although that would be odd to have 2 failures on what seems to be a low failure part, I agree.

 

One other idea. The stupid interior fuse box under the steering wheel which contains the IDS is also involved in all of this.

One 2 Discos, when I've had totally unexplainable electric issues, it's been that fuse box. So, add that to the list?

 

yes 100% repeatable. I unlock 1st time with key and works by fob rest of the day; leave it overnight a d have to unlock with key for the 1st time again.

as I said, I am tempted to buy another RF Receiver and switch it out...but I am afraid I will lose the key coding...even though, in theory, it should not be an issue, since it is a plug and play device. I can’t afford to rent Brandon’s NanoCom again for some time if I screw it up.

I have also heard issues about the interior fuse box going bad...but I feel if that were the case then changing the RF Receiver would have never worked to begin with.

the only reason I knew it was the receiver is because of the obscure “RF Test” procedure in the NanoCom, that when activated, could not get a signal from the receiver.

doc

 

The fob codes are stored in the BCU, the receiver just receives the RF signal and sends the raw code to the BCU. Did you ever have a working fob? Maybe something in the BCU is broken. As @nashvegas hints, test the 12V to the receiver when the fob does not work the next morning. Just connect a wire, let it hang out of the door and test voltage with a multimeter.

 

Well I switched the RF Receiver out with the old one just to see if I could switch it back...without losing the key code, and it didn’t affect that...so it is plug and play and can be switched without losing the code.

so that is a plus!

doc

 

UPDATE:

The “new” RF Receiver got here today; I replaced the previous “new” RF Receiver with this one, and it did not eliminate the problem.

After I use the fob, any of them, to lock the vehicle and let it sit overnight, when I try to unlock it the next day the fob will not unlock the vehicle. I have to use the physical key to unlock it the first time....after that it works flawlessly until left overnight again.

I am completely befuddled by the situation....

doc

 

I just went thru the electrical wiring diagrams. Have you had any water ingress issues ?





IDK here's how I would approach.

Check ground C0707. Remove it, re-secure it.



Check connector C0480/C0485 which is b/t the RF receiver and BCU. Pass side behind kick panel on side of car. Specifically wire in terminal 7 on both sides. Purple / Slate Grey wire ("PS" on wire diagrams). Unlikely but...this is PRIME water ingress areas for leaky windshields or a-pillars...Very much worth a check.




Finally, yellow connector on BCU itself, C0661.





Barring this, or damage to any of those wires above along their runs (I usually suspect connectors first, then lengths of wire for abrasion etc), I'd bet interior fusebox under steering wheel, or some random internal fault in BCU. Sorry, both are super annoying ...but fusebox can be swapped with no reprogramming.

I would remove/reseat all connections on the BCU after verifying the connectors above, and do the same for the fusebox. There might be a dodgy terminal with a small bit of looseness or corrosion that a simple plug/unplug might fix.If it doesn't fix, try interior fusebox replacement, or then BCU replacement (which of course requires programming).

 

Mine does this as well, not sure it's like clockwork 12 midnight it turns into a pumpkin like the Ops. I just assumed it was some kind of security thing sitting weeks without being driven.

 

I have been in process of fighting water leaks above headliner at the windshield. I do NOT have sun roofs (thank god) so my water issue is limited to that area.

so I will check there next; but since it is an issue of “sitting” over night....it’s hard to find it without waiting until, for the lack of a better term, the truck “goes to sleep”.

thanks for the info.

doc