I have read through the threads here and see all sorts of "possible issues". It popped up after my battery needed to be replaced. It briefly went away with the new battery installed-then popped back on. Oddly enough my In Control app started working again and I can now remote start the car. I "thought" it was the SOS lithium battery, so I bought one from Jaguar today (insane its $80 for a small battery) and installed. I then tried to reconnect the SOS system with the button overhead and and yet the light is still on. Does it take awhile driving for the light to go off?

 

Good that you had the old battery replaced. One thing to remember is that "new " batteries that are installed, may not be fully charged. Typically the battery may have sat on a shelf somewhere awaiting its new F. It may take some nice long drives to help the newbie get up to full charge.
May I recommend CTek mxs 5.0? They condition as well as maintain the battery. They come with eyelets for a more or less permanent install and alligator clips for more temporary.

 

Just run a bidirectional OBD2 scanner and clear the error code in the "Telematics Control Unit Module"

https://www.jaguarforums.com/forum/f...module-284994/

 

I don't have an OBD2 scanner. Do they sell one reasonably priced on Amazon? And I have a Ctek and have to say they are a decent company to deal with. Mind stopped working after 3 years, so I contacted the company. They have a 5 year warranty and sent me a new one.

 

is what I and many here use, and the cost is less than the Jaguar dealer diagnostic fee!

https://www.jaguarforums.com/forum/f...attery-281619/

 

It may take a while to fully charge the TCU battery, they come (IME) not fully charged. I think they're only charged when the car is running, so keep the revs up when driving!

 

I will try this route. Unfortunately I rarely drive very far so that is not helping if that is what is needed to clear the code. Thankfully the InControl app is now working again and that hasn't in a very long time. Its nice to be able to remote start the car again.

 

When I replaced my TCU battery it took a few 20+ minute drives before it was charged enough to not give a warning. For 2016 (my VIN, at least) the battery pack is two cells. One is rechargeable, the other not, and I also think it only charges when the engine is running.

I prescribe a longer trip for no reason other than motoring (and charging the TCU battery). Pack a picnic lunch, drive an hour to someplace scenic, enjoy, then drive home. You can trust me. I don't play a doctor on TV, but I do impersonate one in real life.

 

Ha! Well said. I will have to do that. Mine is a 2016 and a dual cell as well. About as far as I drive is 20 minutes in the car, so clearly I need to get some time behind the windshield to see if that clears the code. Much appreciated doc.

 

Sounds like you need to ditch that shortcut and use the proper route!

 

True-but it finally went off. It took about 5-6 short drives and it must have charged the battery.