I do not think I would panic just yet. The battery is a Panasonic nominal 3 volt rechargeable and is probably OK as your battery is showing 3.3 volts.

That is good news so I think you just have the usual crack in the solder joint between the battery and the circuit board so power is not getting to the circuit board. That is probably where those battery people were measuring - on the pcb joint tabs rather than on the battery proper.

The rechargeable vanadium pentoxide lithium battery that you would order is a Panasonic 3 volt VL2330 1HFE but the number may now be changed to VL 2330 HFN. The 1HFE refers to the style of tabs that are soldered on and that there is an insulation wrap around the perimeter of the 23mm diameter coin type battery. The best source is Digi-Key in the USA and they will sell one or two and mail them to you at a good price.

http://www.digikey.com/scripts/dksearch/dksus.dll?vendor=0&keywords=VL-2330%2FHFN

Your comment re the engine still starts is also good news.

If I understand the key fob correctly, there are two circuits on the single printed circuit board. One circuit operates the door locks and requires battery power to both transmit the lock and unlock commands as well as the emergency panic commands and whatever else you may have programmed the buttons to do.

The second circuit on the pcb is the immobilizer circuit. It does not need the key fob battery power to operate. That circuit seems to suck energy and signal out of the ignition key lock cylinder area, (the battery charge function only sucks energy), and then tells the engine computer that the correct key fob is nearby and hence to allow engine start.

 

So, update, started to do some further research yesterday. Local Land Rover dealer is only about 10 minutes from my house - Stopped in there yesterday afternoon. They said they could re-program the key for about $150. But no guarantee this would work. So I may or may not do that - Haven't decided yet. I did a hard reset (disconnect main battery and touch Neg and Pos wires together) - Didn't fix issue. I checked all Fuses - All 'looked' ok.. including #43 in glove compartment fuse box. Lots of different conversations about this issue in various forums mention that the issue could be the wiring harness, which runs along (and underneath) door sills, and is connected to the RF Receiver, which is located above roof headliner and inside the 'dome box' that controls rear air/heat. Apparently this wiring harness, specifically a few green and white wires, can become corroded because of moisture (or in lots of cases actual water), most commonly caused by blocked sunroof water-drainage pipes. Even though the connection of these wires may look ok, lots of people have re-spliced these green/white wires together, and the key-fob remote lock/unlock buttons then work perfectly. Issue with wiring is more common than issue with actual RF Receiver unit. I took the black plastic door floor sills off, and there is another black plastic piece (one for each side of car, serving both front and rear floor) that looks to be held in place by about 4 half inch round white plastic connectors of some sort - I will research exactly how to remove this unit, and then plan to check the wiring. Sidenote - We did have a VERY heavy rain the other day, and when I put my hand onto the carpet of the passenger side (US model, so left hand drive), it does feel ever-so slightly damp, and 'cooler' than I would expect, thus possibly pointing to water damage. Also, we had an even bigger massive rain at around dusk yesterday - Actually a good thing, so that I can do some further investigation around water possibly getting into car. I'll report back with an update. I'll try to 'pay it forward' to this community and take some photo or video footage.

 

When I nout our 05 remote no work , fixed harness splice and it worked, remote could be worn out since everything else on this fails prematurely

If I were you I would pull the pass sill and kick panel to look for water intrusion, if evident look for blue tape, give a light tug to those wires if they come apart u need to strip way back to clean wire or do like I do dip in acid to clean then solder and shrink tube

Water ingress is easily fixed by blowing out sunroof drains, sealing a pillar covers and checking hvac drain boots

 

This link shows the splice you are looking for.

DISCO3.CO.UK - View topic - Remote Locking from KeyFob not working (Again)

At the bottom of the thread are a couple of good pictures of the splice and where it is located in the big wiring loom. This was on the right side but I think there are two splice locations, one on the right for the right side doors and the other on the left for the left side doors.

I note that TOM R said he repaired the splice located on the passenger side of his North America spec 3 so that is where you should first look.

The splice can be hard to find but it is there. My view is just assume the connector has corroded and redo the splice - you are dealing with corrosion and that is not like an oil leak or similar.

If you had a second key fob and it worked, then the problem would not be splice related but as you do not have a second one, you pretty much have to investigate the wiring as well. My view is that fixing the splice is much easier than fooling with software or circuit boards.

My guess is that more 3's have the wiring issue than the key fob cracked solder joint.

 

Update - I have just finished examining the Passenger side (U.S. vehicle) bunch of wires, and I do not see a splice pertaining to any green or white wires. I do see a splice connecting some red wires, which are apparently for the 'door switch lights'. There is absolutely zero sign of water damage in or around the channel where the wires are sitting - Some dust in a few places, and a few very small particles of dirt. I guess this 'dust' could be from 'dirty' water that has somehow got in there and dried, but I don't think so. Partly because some of the white paint looks absolutely new and clean. I have no other signs or symptoms of leaking sunroof drainage tubes, and I checked the cabin air filter, and don't see signs of water. I did buy a new keyfob battery by the way, and it arrived today. I don't plan on trying to re-solder this new battery unless I am more certain that battery connection is the issue. I now plan on examining the driver side wiring, to try to find the white/green wire-splice. My vehicle is a 2008 model - Can anybody report with certainty that a 2008 model does or does not have this green and white wire splice on passenger or driver side of U.S. model LR3? Thanks, Simon.

 

Update - Still not fixed. I examined the driver side wiring, and did not see any green/white wires spliced together. I did however see some Yellow with Brown and Yellow with Black wires spliced together. But I don't think I'll re-splice those - Everything else on vehicle is working fine (I think!). I've attached a photo of these wires though, just in case it's somehow relevant to my issue. Sidenote, there was a small amount of white powdery material on some of the wires on driver side - Probably dried salt, probably from winter. But I did not see any evidence of water damage. With the heavy rains we had a few days ago, I certainly would think that I would have seen some signs of wetness in the door sills areas, either on driver or passenger side of vehicle - All completely dry. I took off the rear roof mounted HVAC control panel to access the RF Receiver, and I think I found it - Mounted to underside of rook, with 2 wires coming out of it (connection was fine). Looks like I need to remove headliner to be able to remove or test RF Receiver - I haven't done that yet. One of teh wires was dark green, and the other had 4 alternating colors - very light yellow and dark green. I can see how this very light yellow could be mistaken for white. These 2 wires went over to left (driver) side of vehicle, and then down the pillar between front and rear seats, with some other wires, and then did a right angle and travel beneath carpet to passenger side of vehicle. Then another right angle along floor / door sill area towards front of vehicle. I examined the passenger side wiring again - did not see any wires spliced together. I guess there could be a 'slice' in an area that I can't get to without removing seat - See photo of 4 inch light grey metal 'bracket' that sits over a plastic 12 inch long corrugated 'sleeve' that goes around all of the wires - Do you think the 'splice' could be in there? Unless I get additional good advice, I think I will resign myself to the Stealership - I have an appointment for first thing Monday, and apparently it will cost about $150 for them to 're-program' the Key, which may or may not fix the issue - They said we should start with that... Final question - I would REALLY like to test the RF Receiver - Can someone give me step by step instructions? I have a multi-meter, but I'm absolutely useless at anything electrical, so any advice would need to be very basic! Thanks everybody.

 

Me again, not giving up... So, I said I'm useless at electrics, so be nice to me - I used my multimeter, set to the '20' DC Voltage setting, to test voltage of the 2 wires that connect to the RF Receiver. Not sure why I did this... Anyway, I was able to pull out the small black connector that plugs the wires into RF Receiver without removing the headliner, and the reading I got with engine running, with multimeter black probe touching solid green wire and red probe touching green/white wire, was 0.85 volts. And with engine off and key not in ignition, the reading 2 minutes later was 0.54 volts. What does all of this mean? Should I pull down headliner and remove RF Receiver and do further testing?

 

I would go back to digging thru the passenger side wiring bundle. I still think there is a splice there and it is the problem.

I must say however that you have been very diligent in your searching and I am wondering what the yellow twisted pair are that you found. The twisting of the wires infers that those wires are part of a CANBUS circuit not related to your current problem.

The wires to and from the RF receiver are however normal wires but probably too thin to be reliable but electrically in theory sized large enough for the digital signal they are designed to carry. I have heard of others looking for the splice and initially not finding it as it is truly buried inside the bundle. It seems everyone finds the red wires however.

If you do find that green white splice, regardless of what it looks like, I would be cutting it off and twisting the wires back together using a simple electrical Marette.

The low voltage numbers are OK, in fact I am surprised you got any reading at all as for the most part, the signals in and out of the RF receiver are some sort of low voltage digital signal per the note below.


The RF receiver converts the signals from the remote handset into digital messages and transmits them to the CJB (central junction box) . The RF receiver is installed above the headlining, on the cross-rail between the top of the B pillars.

Operation of the RF receiver is powered by a permanent battery feed from the CJB (central junction box) .


As for the voltage remaining when all seems off, the door lock circuits tend to remain alive awaiting an unlock signal, (or lock depending), and are also a portion of the alarm system. Note the comment above re permanent electrical feed.

 

Thank you bbyer. You've answered more than one of my posts regarding this issue, so I guess it's now a 'team' effort, so feel free to fly down here and help me strip teh entire vehicle apart. Thanks for the RF Receiver voltage explanation - That makes sense, i.e. probably nothing 'broken'. I searched again on teh passenger side for where the green/white wires join together, and I did not find it. My vehicle is an 08 model - I wonder if the spice is in a slightly different place. It would be great to hear from people who had this issue with 07, 08 and 09 models, regarding whether the wiring splice is in the same place. Less than 24hrs before I need to drop off a large bag of gold at the Stealerhship and let them try to fix it - Less than 3 miles from my house, and 6 years of Land Rover ownership, and I have never needed to spend a single penny there - I apologize to my friends and family if my behavior is slightly 'off' this coming week.

 

It is possible that by 2008 that LR had finally updated the wiring loom to what it should have been - telephone squeeze splices really do not belong even on an English production line.

I regard the 2008 model year as the best 3 made. In 2009, they started to experiment with systems they were considering introducing on the 4 for the 2010 model year. The 2008 vehicle embodied all the fixes that they had learned over the years, hence it was time to start messing about again.

It might be that the cost of a new dealer provided key fob might be about the fee charged just to write up a work order to find and perhaps find the problem. Actually if the dealer can solve the problem on the first attempt, you will be very fortunate.

I regard a second key has important to have and if for some reason the new key fob solved the problem, you would be ahead of the game - a thought.