My 2006 X150 started making 'clicking' noises two years ago.Having gone down the route of buying a new battery (many people say that a tired battery causes all sorts of electrical problems)
I finally deduced that the noise was coming from the alarm module - which is hidden under the pedestrian airbag under the bonnet on the drivers side.
Jaguar at that time said the part was NLA so I sourced a second-hand one on ebay for £35.00! This has now failed and on taking the unit apart - the PCB which is inside the metal housing and inside a sealed plastic casing is shot! Either the rechargeable battery inside the unit has fail;ed and acid has destroyed the pcb or moisture has formed inside the scasing and had the same effect!!!
This is exactly what I found with the original unit - so NOT a simple battery replacement inside the unit.
Jaguar I believe still use this unit on the XF and XE cars so I will try them again - though suspect I will be need to be sitting down when they give me the price - if it is available as a spare part!!
Other manufacturers use the same module eg Volvo, Ford etc as can be seen from the second hand units that appear on ebay.
Why oh why do Jaguar use such crap that only lasts a few years on a £60000 car? Chinese manufacturing springs to mind!!
Does any one out there know where I can buy one of these units - NEW - at a sensible price please?

 

If you post in the forum for your car you will get better answers as this is for the 2010 and up XJ.
So the cars are different. Not sure our cars even have this?
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