Hello, all.

I recently purchased a 2016 LR4 Silver Edition with HD package. The truck has 74k miles on it. I bought it from a friend and it has a known problem so I got a decent price on it. But this known problem is kicking my butt.

The vehicle has the dread "smart key not found" error. This started happing when my friend owned it seemingly randomly. He took it to his indy shop, which sent him to the LR dealer. And he and I have both replaced the key fob batteries multiple times.

The dealer replaced the battery, battery module, the KVM and wanted to throw a new BCM at it. He was $3,000 in replacing modules that didn't solve the problem and declined to replace the BCM (understandably). The dealer was just throwing modules at the wall hoping one would stick.

JLR even got involved yet it's still a mystery.

When I looked at the truck I discovered that the sun roof was leaking all down the A-pillars. I fixed that issue, gutted the front head liner and A-pillar trim and started looking over all wiring in the path of the water. Nothing remained wet by the time I took it apart. I'm in AZ and moisture doesn't stick around long.

What I did find is that this problem is intermittent. So every time I get in the vehicle I try the key in my pocket, when it doesn't work, I use the under column method to start it. It will work fine for a few hours, then back to the key not found error.

This thing has tricked me into thinking I fixed the problem a few times. Now I just periodically hit the unlock button to check if it's working. I have a used RF receiver antenna for the KVM system coming so I can try that. In the mean time, I'm wiggling wires, try to unlock, check grounds, try to unlock, etc.

Odd thing is, it seems to often start working at night and then the next morning it doesn't work again. But it's so random I can't find a correlation with anything.

Last night I removed the passenger side kick panel to reveal the wiring from the fuse box and BCM, wiggled a wire, hit unlock and then it started working. I fixed it! Nope. This morning, I'm back to the key not found error.

As an extra bonus, the physical key on the driver door does not unlock the vehicle so I can't lock the truck at all (had to break into it once already when my wife locked it and then the key failed again). I do have a new lock cable coming so I can at least fix that problem.

Has anyone dealt with a similar issue? It's driving me nuts.

 

To add to this. I did finally establish a pattern and it's a weird one.

The key not found error goes away completely after about 4pm. For the last few days, in the morning I get the error and all throughout the day. In the late afternoon it just starts working and the keyless system will work flawlessly all night long. The next morning, back to key not found.

Riddle me that, Land Rover. Is this thing just a night owl?

 

I realize I'm just talking to myself here, but, I have established that the key not found error only occurs when the cabin of the vehicle is hot. Driving around with the AC on, the key works up to about an hour after. Once the interior gets hot, not more key. At night, the cabin is cooler and the key works. I'm in AZ and we have 105+ degree summers so the interior gets hot quick.

Also, I cleared all DTC codes and the only one that pops back up is B102B-87 - Passive key error which is being reported by the BCM.

 

Again, nobody has chimed in on this yet, but I'm going to keep documenting this super weird issue here.

Because this key not found happens only in hot tempretures, I decided to try to isolate the problem. I pulled the truck nose first into the garage, letting back half of the vehicle bake in the sun. After an hour I went outside and hit the unlock button. Nothing.

I then backed the truck into the garage exposing the front to the sun and the rear to the shade. After an hour, the unlock button worked. Bingo. The problem is somewhat isolated to the rear of the truck.

Because the KVM was replaced already, I haven't gone to the trouble of pulling the quarter panel trim to look at it but today I did. And I found something very strange. Someone hacked a wire in the KVM harness.

For some unknown reason, there's a very out of place white wire tapped into the KVM harness that goes up into the headliner. The only people I know have been in here is the local LR dealer. I called and they have no notes about a wiring harness bypass.

If I were a tech and saw that, I would be documenting that for CYA purposes for sure. I'm suspecting they are the ones that did it. But I have no idea why. I'm going in tomorrow to show it to them.

And, there's power to both the out of place white wire and the one that was cut. Strange stuff. I only wish I had the resources to figure what that wire does.

 

Well, I figured out the problem on this. Took a while but I'm pretty sure it's resolved. I followed that out of place white wire up the headliner and found that it terminated at a little black box that's velcroed to the roof. Like to the actual metal of the roof.

This got me thinking maybe this box, which turns out to the keyless entry antenna, is overheating and causing my problem. I pulled the little box out off of its mount and hung it inside the vehicle.

All day today it worked fine. No key not found issue. That box was mounted to the roof which can get super-hot and it was just failing from the heat, then when it cooled off, it worked again.

I ordered a replacement and I'm going to fasten the new one to the headliner instead of the metal roof. This is just one more thing to check if you get a hard to diagnose "key not found" error.

 

Thank you for posting this and your analytical method to find this. Hopefully no one else runs into this issue, but if they do, you have done a solid service for them.

Wilybyrd
'10 LR4
'24 D130

 

I am experiencing the EXACT SAME ISSUE all of the way down to the physical key, not working to unlock the door. I too have had to break into my vehicle once that was a nightmare. It’s bad that I’ve had to live with this for the past eight months but what really gets me is that I can’t even lock my door when I go somewhere and my car has been rummage through all three occasions now it is maddening. I have sought help. I everyone seems clueless. What are we supposed to do?

if you have found out any new information at all, I beg you, please reach out because I am desperate at this point to get this resolved.

 

For me the problem was a bad butt connector where some JLR tech did an "overlay" to fix the actual issue. Basically, there was a wire cut somewhere that goes to the keyless antenna and they spliced in a replacement wire. I'll bet your wire is severed too, also needing this same replacement wire. It's hard to explain but if you want, I could make video explaining it.

 

Great troubleshooting and work. Definitely good info for others.