After replacing front rotors and pads on my 94 xj40 my electrical system was completely dead. The only things working were the radio and park lights. I installed a new battery with no change. Even the dash and warning lights were dead. Cleaning the battery and ground straps did not help. What could
I have done to cause this? Inertia switch?
Check the ground points around the engine bay. You could check the inertia switch but if I recall correctly it just shuts off the fuel pump.
Jim.
The Inertia Switch is a good candidate since the radio and sidelights do not need ignition switched power to operate whereas the other things you are missing of course do.
Have you tried to re-set the Inertia Switch (driver footwell)?
If not that, could be the Ignition ON relay (black base behind radio)
Finally located the inertia switch. Solved the no start problem.