Our 2013 XJ Supercharged has recently had a flashing drivers display and headlights upon starting. It lasts for about five seconds, headlights also flash.
Hard to reproduce so dealer has not been helpful. Anyone had a similar experience? The display cycles between graphics of speedo, tach, words, lists.

 

How many miles on your XJ? Do you leave your key in the car when it's parked in your garage? If not, do you lock the doors when it's parked in your garage? Leaving the key in the car prevents convenience mode from completely shutting down, which causes continuous power draw and running down the battery. Not locking the doors increases the time that convenience mode stays on.

Late model Jaguars are notorious for problems caused by low battery voltage, including the X351. Search this forum for "low battery". Many owners on the X150 Forum (alloy-bodied XK/XKR) use a battery maintainer to keep their batteries fully charged. I use a CTEK MUS4.3 on my 2013 XJ and have never had any electrical gremlins: https://www.jaguarforums.com/forum/x...lation-130801/.

My guess is that your battery is low, and after 5 seconds the alternator has it charged up enough for the display to work properly. If you have a voltmeter, you can do an easy preliminary check: with the ignition OFF, there should be at least 12.2 volts across the battery terminals. If not, you need a new AGM battery. If that's OK, I'd have both batteries (large primary AGM and small secondary stop-start) load tested. Then I'd make sure the charging system is operating properly.

 

Stuart's suggestion is the place to start as you have classic dying battery symptoms. The AGM batteries and relay priority used in these cars are able to crank the engine right down to voltages that are otherwise well below what the systems need to run. If still the original main battery it is time for a change now anyway, but do check the charging system and as a 2013 should still be under US warranty then have the dealer perform a shutdown drain test to ensure there is nothing wrong there.

It would be worthwhile to disconnect the negative terminal from the battery for 30 seconds (it will remove the battery monitor with it) and then reconnect to hard reboot all the modules in the car in case one is going loopy and holding the rest on. (I have experienced that with a TV module that got stuck on and kept sending CAN messages and would drain a fully charged battery within 48h.)

 

My XJ has 26543 miles on it. We park it in the garage with windows open, unlocked, keys in the house. We have owned it for two years without this issue. It still has the original battery from Italy, per the label. I did measure the battery voltages at rest and the main battery was at 12.2v and the small battery was at 9.7 v. With the engine running both batteries were at 14.3 v. So i disconnected the start stop small battery negative cable. I hate the ECO mode anyway so this just cements my disconnecting it (actually removed the negative cable from the car). I am going to NAPA tomorrow to buy a AGM battery, made by Penn State, and replace the main. Our service advisor had mentioned the low battery voltage could cause these issues, but I have always been leery of their advice. I do most of my own maintenance and have had BMWs for the last 35 years. This Jaguar is our anti-flying mobile ( I traveled too much in the air for my career) and we love it. I am not used to computer displays for primary auto displays although I designed many for military aircraft. But our displays were truly mil spec and did not exhibit this type of behavior. Thank you for you inputs as I appreciate the confirmation that I don't have a singular failure and have been wary of Jaguar's past issues with Lucas electronics .

 

As your main battery is low you should use a suitable AGM battery conditioner/charger to fully charge it if you can before swapping it over, otherwise the battery management system may fail to detect the new battery can hold more charge and give you warnings and shut down certain non-essential systems until it has recalibrated itself. If you don't do that you may need to drive the vehicle around for a few days to put enough mileage on it for the module to self-calibrate. (It is important not to use a battery charger that exceeds 14.3V as that can damage AGM batteries.) If you get problems after the change and can't get it to calibrate then your dealer can hook it up to their computer and do it that way.

 

Is this what you are experiencing? I just had this issue fixed. Will need to look at the receipt to get you the module/part #s...

 

Here are the part numbers for the fix:

Jaguar Picture by Purple Panther | 5983818 | JaguarForums.com

Hope this helps you (and anyone else who encounters this bizarre error light show)!

Scott

 

The new AGM battery has been installed now for three weeks and the issue is gone. Thanx for the help