Our beautiful 1996 XJ6 4 liter will not start. It has been sitting a long time, 2 years. I kept a battery maintainer on it the whole time. It ran fine before we stored it. Always started. Has about 140000 original miles on it. All the lights come on, everything seems to work, but when I turn the key to start it, lights go dark and nothing. I don't think there were any mice to chew wires as I found no nests under the hood, but that may still be a possibility. Any suggestions would be greatly appreciated. We put a ton of work into our Jag back in the early 2000's to restore it from the neglect of a previous owner. I'm now 75 years old and my physical abilities are limited but I am still sort of capable. I am an engineer by trade and a long time auto and motorcycle enthusiast (I still ride and used to drag race cars and motorcycles) and have lots of mechanical ability but bending/leaning over to turn wrenches and jumping under and up is limited these days. I can do it, it just takes me more time now... but I am retired so time is sort of on my side.

My other car is a 1975 Porsche 914 I got fed up with the VW 4 cylinder engine and just a Buick V6 in it. Of course that was back in the late 1990's that I did all my own work on the conversion but things like that you never forget what it took to complete.

Any thoughts on where or what to look for first on my Jag would be greatly appreciated.

Don

 

Aside from electrical the fuel should be drained and replaced

Fuel filter change ?

Do you get starter rotation ?

Starter voltage sag ?

In the initial start sequence the fuel rail is charged with fuel pressure for 3 seconds then fuel pump off

The fuel pump comes back on for the duration of your drive with the CKPS seeing rotation after a certain point

The fuel rail can be charged by rotating the key a couple of times without rotating the engine

Another thing that can happen from storage is the compression can lower to support a successful light off and this is referred to as a bore wash

Lights go dark on key rotation / age of the battery ?

Never install the battery in backwards , positive post goes fwd with car direction of fwd travel

Never over tighten the battery positive post bolt , breaks the nut underneath

Ask questions as we define the issue and determine the factors of consideration

 

If she doesn’t crank, electrical would go to the top of the list, and for me the battery would be at the top of the list. Although you say you used a maintainer, I have some experience of stored batteries showing on the maintainer as ok, but having lost their oomph. Simple enough to try jump starting to see if it helps?
Thereafter checking connectors and earths in the engine bay would make sense, and given how easy it is to do, I would check the inertia switch, although you haven’t mentioned anything which would suggest it could have been triggered.
Once you have her cranking, you may well have fuel issues, but we can cross that bridge if you come to it.

 

In storing the vehicle the Security Lock Control Module fuse may have been removed to keep the alarm silent

The SLCM must be powered for starter enable

Fuse # 4 in the trunk

Might as well do a fuse check against page 21 of the below Doc

jagrepair.com/images/AutoRepairPhotos/X300 1996 LWB.pdf