My 1991 XJ-6 was running at idle in a parking lot...I went to drive on and turned on the headlights, (it was a rainy day) when all of the sudden the car totally dies...No electrical power what so ever. After I few minutes, the electrical power came on again, and I was able to drive away. As stated, all power dies completely...Almost as if we took the battery right out of the car. Help!
Electrical Problem? on 1991 Jaguar XJ6
Check the battery connections are clean and secure. There is also several insulated studs or posts Jaguar use to carry power. Follow the heavy power cable from the battery positive terminal in the trunk I think that one is beneath the battery. In the engine compartment passenger side you will see another heavy black colored power cable its got a black rubber boot over it ensure these connections are tight. I have sen them loosen and do exactly what you describe. Jaguar has a technical service bulletin about this problem.
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Battery tearmals loose or light socks are hork up right