Hi. In 2016 september, my jag (xj6, X300, made in1996, 4.0L) was crushed from rear. So the trunck was completely destroyed, but the electrical parts there (battery, module, fuses etc.) were not affected.
Now I repaired the car, but it still not crank, even the mechanics press the impact button (the one which is located at the right foot of the right passenger - my jag is left side drive), even I put the gearbox in the P position, even I replaced the key fob's batteries, even I tried to reprogram the key fob...
Can you help me with an advice? Thank you.
PS: Of course, I filled the tank with gas and I replaced the oil in the engine.

 

From what I understand the crash switch is fickle to reset as the internal parts to the switch are delicate

The switch can be bypassed with a paper clip in the connector on the 2 white wires

Do you have fuel [ump for later in the starting sequence ?

In the heat of battle watch the battery gauge that it does not sag below 11.4 volts

 

Ok, thank you. In the tank is enough fuel and the fuel pump works three years ago....

 

Today when you rotate the key , do you get the 4 second on then off to prime the fuel rail

But first things first / starter rotation

There is a connector in the trunk better off leaving alone for now that carries the starter enable wire from the trunk mounted security locking control module to the body processor module

This BPM commands the starter relay to close for the starter solenoid on the starter to do it's thing

Do you have a good battery connection ?

Just fwd of the positive battery post is the fuse link and the fuse link terminal nuts intact ?

A point to test on the starting is weather the starter relay gets the command ground which will make the relay click but you must put your finger on it

See page 17 in the LWB pdf below as relay # 4 LH engine compartment

Does the small relay in the corner of the trunk fuse box click with your finger on it with key rotation ? this relay brings power to the trunk fuse box

It can be tested yourself by leaving the key on and removing it from the socket and feeling it click closed

 

Thank you very much.
I checked all the fuses and the relays at the engine and in the trunck, and all of it is ok. The battery is new.
When I put the key in the ignition position nothing happens but SRS/Airbag intermitent light on the dashboard... So I will bring the car to a Jaguar Dealer Service, in Bucharest (I am from Romania).

 

Now we get to the large connector above the fuel tank that carries the wire from the SLCU and the BPM

It may have become unlocked and disconnected

It is a hard connector to get right as there is interference on the sheet metal to seat correctly to engage the locking pins

As you carefully pull the locking bar over it can be held in place with a ziptie or tiewrap

You want to be careful not to break the locking pins