Hi Everyone,

I'm hoping someone on this forum has a more in-depth electrical knowledge of modern Jaguar's than I do, as I have a really puzzling problem that is extremely frustrating. Car was running fine until I attempted to repair (or at least check) for non-operation of cruise control. I eventually concluded that the ECM was not sending an earth signal to the steering wheel switch (which also serves the adjacent radio controls). This earth should be provided from pin 13 on ECM. I removed the socket from the ECM a number of times to check and since then the car sometimes will not start (ignition lights will come on but engine will not crank). At first I thought it was a poor connection between the ECM and its socket. However, after removing the insulation from around the input I found a small round metal tube with a green and a yellow wire wrapped around it in a coil fashion. I formed the opinion that it was perhaps to do with the immobilizer system (??) and that it was creating a magnetic field for some reason (??). Near to the metal tube is a white and a blue wire, which (via the loom) go to the electronic egr. I have found that by moving these two twisted-together wires slightly the engine starts and continues to run, until I move them again slightly, at which point the engine stops (???). I have checked these two wires for continuity and they appear fine, even when wires are moved. Looking at wiring diagram these wires are part of the Canbus system. I am now wondering whether the wires are receiving electrical interference from other surrounding wire, or indeed from the metal tube (which presumably becomes a magnet ??) Does anyone have any ideas what the problem could be - I'm pulling my hair out (and I don't have much left anyway) ??? Thanks everyone.