I own a 2005 X350 XJR with 90,000 km's and it is brilliant - however I would like to hear from anyone who may have experienced a similar issue with the touch screen display not waking up immediately after the car has started.
I have found when starting the car in the mornings that the touch screen display soft buttons and hard buttons on the side take several minutes of driving before coming to life. Once the TSD comes to life all the soft buttons and hard buttons on the side of the TSD work fine and are fully functional.
When the touch screen is blank and I use a WDS tool to download any DTC codes, I find the U1262 code related to SCP network circuit fault. After clearing all the fault codes and once the TSD comes to life along with both the soft and hard buttons, there are no DTC codes present.
I have used the ICE Head Unit diagnostic menu also once the touch screen comes to life and there are no fault codes recorded to reflect the variable wake up time, or a SCP network fault..
During the period of delayed wake up of the IHU, I have found the radio, the voice command, and A/C working as per the settings when the car was shut down the night before.
During the day of driving and after the initial start up, the IHU will come on straight away as "normal" on starting the car after multiple stop and start cycles.
I have checked the battery.
I have examined the D2B fibre optic cables and some connections that make up the SCP network and because the car only has 90,000 km's, I believe the D2B domestic data bus network be in very good condition.
The matter of interest - why the extend time for wake up of the IHU given once the IHU and touch screen display comes on there are no functional problems for the rest of the driving day??
Appreciate any thoughts to potential causes

 

The problem described in my post above has been resolved. After taking the car to an after market jaguar technician the diagnosis focused on a fault in the IHU ( the sat navigation touch screen display unit in the dash). I was able to source a very well recommended euro car electronics repairer, so I removed the unit from the car and sent it to them for a bench test and repair. They were able to change some components and repair dry solder joints on the circuit board. Once refitted to my car all systems worked fine.
The learning here is that the sat navigation touch screen display unit does in fact fail from time to time - so it you find there no obvious fix have the unit bench tested by a electronics repair guy, and save your self a lot of time and money.