MY2018 F-Type R.

Anything I can further try to resolve the code? Is it expected that a code is thrown when the module is reconnected & that the dealer would have to reset it?

I located a buzzing/rattle inside telematics unit, adding some insulation inside it around the circuit board metal plate and making sure the buzzing is gone which was very satisfying. I was careful not to damage or disturb anything.

I turned on the car WITHOUT the module plugged in and got the SOS System Not Available. Car would not start which I later learned is by design if SOS is disconnected.

I then plugged in the module connectors, turned on and got SOS Limited Functionality. I took a guess the module's small battery might have needed replacement and bought a new OEM (part LR089861) one since it was $17, however after replacing it and driving the code does not go away.

I tried reconnecting the main car battery as well as charging it with CTEK MXS 5.0 overnight.

I also tried an OBDLink MX+ reader but it didn't see any codes and clearing DTC didn't help, likely because this is an OEM DTC instead which I don't know of any personal use OBD reader that could see these codes.

 

Although the 'SOS Limited Functionality' error message appears for various TCM related faults, I've not been able to identify any DTC that is logged (iCarsoft using Jaguar interrogation mode).

The main 'SOS Limited Functionality' issues with TCM are:

1. Lack of signal for the built in SIM card to connect to Jaguar InControl services.
2. Discharged rechargeable lithium battery.
3. Disconnected centre speaker - yes really. MY2018 onwards use the centre dash speaker to provide inbound communcation from the InControl emergency services. The TCM has a detection routine to check continuity of centre speaker and will throw up error message if centre speaker not detected. Even if you have base or Meridian 380W sound system, you will also have a centre speaker exclusively for telematics.
4. Error with the TCM itself - unfortunately my case. Expensive out of warranty repair

Any work on TCM needs to be concluded with reset routine to establish communication with InControl services. See linked video from 6:30 onwards -->

 

Excellent video, thank you!

In my case I happen to be in the middle of upgrading all my speakers to the super premium meridian ones so the center speaker is not yet connected! Interestingly I get no audio from the center channel with the stock or new speakers even though I have the AUD4-16 / PREM 16 audio (Meridian Surround, Dolby etc) which should work. That's a topic for another thread.

I did plug the center speaker back in and the issue didn't go away even after trying the your hold down service key reset. I tried it a few times with and without engine on.
What worked was to additionally unplug the battery and so far the SOS light is gone. Now I had unplugged battery alone a few times prior so that alone was not enough.

So the secret combo is likely all 3 combined:
1) center speaker connected
2) service light reset hold
3) re-connect main car battery

I'll keep an eye and see if it resurfaces and how it reacts when I disconnect the center channel again for upgrades/debug.

Thank you sir.

 

I tried to replicate the issue and fix, so far unsuccessfully.

You are correct that unplugging the center speaker is enough to trigger the code.
However hold down to reset (fast blink until slow blink) doesn't resolve it currently.
Nor does reconnecting the main battery.

Maybe there's some additional timing/sequencing for the TCM (TCU?) reset.

 

I don't know of any further 'user' reset procedures for TCM. It could be that you have damaged the TCM when opening it up to address the buzzing issue, or that the buzzing issue was an indication of a failing TCM. You also mentioned that you did not get audio signal from centre speaker when DSP was set to surround, so centre speaker could be blown/damaged. Either way, I think you are now at the stage where dealer or independant specialist diagnostics may be needed to resolve the issue. Good luck and keep the forum updated.

 

The guy in the video isn't very bright if he didn't know the SOS button calls the emergency services - it's stated pretty clearly in the documentation. Always get to know your car before using it!

 

I confirmed that the speaker itself is working by connecting it to the door instead for testing. It just doesn’t play audio when in the center dash.

So that leaves the connector, connection or telematics unit. Will keep experimenting.

 

My light came back on after changing the battery and pushing the service button until slow flashes... About a month later it went off and has stayed off... Another thought might be the replaced battery was not charged sufficiently, and after some driving it has come up to the required voltage... These are rechargeable batteries and depending on how long they've been on the shelf they do tend to lose charge... I've read they don't charge when you charge the main battery, only while driving...

 

I got the limited SOS warning when my telematics battery got old. For my model year, it's a double battery pack, one of which is rechargeable. It took a little driving to get the new one charged up but it's been fine since.

As for the center speaker, I would not expect it to be able to trigger an SOS system fault, but that is clearly the case. I do recall documentation saying that not all audio modes use it, although I haven't read through the audio system manual since 2015.

 

In my case I just installed a brand new TCU battery so it can't be that either. I did charge up the car battery overnight as well as go for a long drive.

 

Actually, it could be that. As I noted, my new one it took a little charging up before the alert went away. Maybe a few 20 minute drives? I can't recall. I probably commented on the thread about "SOS Limited Functionality" where we discussed the batteries in more detail. It might also be that you have a different battery. There were a couple of choices when I needed one and I had to match the VIN.

As far as I know, the main battery has nothing to do with the SOS warning, although conventional wisdom here is that a low battery can cause just about any problem imaginable.

 

@pistol Can you give us an update on this vexing problem that spans all Jaguar and Land Rover forums?

 

I found the solution thanks to a post by skyking over on the F-Pace Forum: https://www.fpaceforum.com/threads/t...st#post-738389

If the "SOS System Limited Functionality" warning does not go away after replacing the TCU battery (mine was 7 years old) and driving around for a while like it did for @lizzardo, then you need to clear the error code using a bidirectional OBD2 reader. In my case I used an iCarSoft V3.0 and it worked great.

What about the center (or "centre" for our UK friends) speaker issue? Remember the center speaker is not for surround sound but for the SOS system to be able to talk to you if power is out after a crash, malfunction, etc. That is where the TCU battery kicks in.

Well I can confirm it will also identify if the center speaker is disconnected for those SQ enthusiasts upgrading their stereo and replacing the center speaker.

Many thanks to @Jag Bass for warning me about keeping an electric load on the TCU with an AudioControl LGD 60 (or rewiring the oem center speaker to another location such as the glove box). Otherwise the "SOS System Limited Functionality" pops right up.

Yet another good reason to own a bidirectional OBD2 tool for these finicky cats!

 

Nice work @JagCode3 As part of my own "SOS System Limited Functionality" issues, I also used my iCarsoft reader to try and identify any stored DTCs. In my case, no DTCs were found (in Jaguar diagnostic mode, rather than basic OBD mode). Can you confirm what DTC you found logged relating to the SOS System Limited Functionality? Or was it a case of you just ran a 'clear all error codes' using iCarsoft?

 

@genp729 I did the Auto Scan which identified the Telematics Control Unit Module had a fault. The TCU Module is second to last in the list. I then entered that module and erased the code. I had to do it two times for it to stop. I hope this helps!

You can also "clear all the error codes" too after making note of them as many are intermittent historical events.

Please let us know if this worked for you.

 

I did Autoscan and clear all codes meany times with Pathfinder which didn't help, thus I am suspecting a physically faulty TCU since I had opened it to fix a buzz.

The AudioControl LGD 60 sounds very interesting, I just ordered one to try. I wonder if I could connect it to the Center speaker plug on the TCU side as a way to confirm if the issue is the TCU or the actual harness between TCU and Speaker, because I have already tried 2 different center speakers as well as confirmed those speakers work (when plugged into door harness instead).

Pathfinder TCU DTCs are:
- B1A01-13 - Speaker #1 circuit open
- B14A9-13 BroadR-Reach Link - Telematics (+) circuit open
- B14A9-13 BroadR-Reach Link - Telematics (-) circuit open
- U2300-56 - Central configuration - Invalid / incompatible configuration

I have not been able to reflash the TCU (via Update ECU or Replace ECU) with Pathfinder even though there is newer firmware.

Sometimes it's TCU
- B1A01-11 - Speaker #1 Short circuit to ground
Together with AAM
- B128C-11 Speaker #15 - Short circuit to ground, #15 here is actually CTR as numbering is different.

At the same time since I did take out the center vent to get to the speaker I also have HVAC
- B1413-87 - Centre Vent Motor / Actuator - missing message

 

Those codes lead me to believe it is a wiring issue in or out of the TCU. The HVAC center vent error means the plug in the front as you lift out the unit is disconnected or my be damaged.

Perhaps completely unplug your TCU and remove it then inspect all the wiring going in and out to make sure there are no kinks or other damage. Remove the battery too. This would also reset it. Disconnect main battery too. Then reinstall and clear the codes.

See if the TCU communicates with the InControl app for remote functions. I had to renew my subscription to get this to work but was relieved when the car pinged after several minutes of searching.

Good to have you back @pistol

 

I will try it thanks. How did you renew the InControl subscription? Do you use an AT&T sim with it? I don't have an active sub (used car purchase).

 

The TCU has its own SIM, no need to buy one. I took out the old SIM from my center console, and the car still communicates remotely and can be locked from my phone.

Just download the "Jaguar Remote" app and set up your car VIN and your name, address. If the previous owner hadn't deleted the car from their account you will need to call Jaguar to update ownership. The renewal was something like $120.

If the app communicates with your car the TCU is still functional.

There are some good YT videos about activating and using the app.

Did you remove the TCU and recheck everything going in and out yet?

 

Thanks for this video! I received the SOS Limited Functionality Message yesterday! Expected having to go to the dealer, but checked the Forum, and found this video! Followed your procedure and removed battery. I didn't think replacing the battery would solve the problem, because it measured at 4v dc! I looked on line, but didn't find anything I wanted to take a chance with! Called the dealer, and not in stock. Had to pay 60.00 and order it! Expected a long wait, but got the call this morning! Much to my surprise, put the new battery in, and presto no more message, and didn't have to reset anything! Thanks again!