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Richard, Jaguar Technician
Category: Jaguar
Satisfied Customers: 15307
Experience:  12 years at a Ford/Lincoln Mercury and Jaguar dealer as technician and shop foreman.
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Jaguar xj8 with a dead battery. Only have the valet key, and

Customer Question

Jaguar xj8 with a dead battery. Only have the valet key, and cannot enter the trunk. Any work arounds to jump start the car? I did find the key lock for the trunk and the valet ket will turn the lock, yet the trunk will not open. I hooked up the jumper cables to the 80amp fuse and grounded them via the strut housing. The battery was dead because I left the parking lights on all night. Now the battery is so weak, the interior lights will not come on and all faults are coming accross the dash in the lcd odometer area. If I keep charging the xj8 via the 80 amp fuse,, and keepp the ignition on, will the voltage make it to the battery, so I can start the car; or at least opn the trunk?
Submitted: 6 years ago.
Category: Jaguar
Expert:  Richard replied 6 years ago.

Hello and welcome to


If you jump or charge that fuse this should get you enough power to open the trunk with the switch on the trunk lid or dash. You should not keep the ignition ON as this will run down the battery voltage.

Customer: replied 6 years ago.

MY car has been in valet mode, so the trunk or interior trunk button does not function. If the battery does build up unough amperes, can the key be used under the trunk lid, and if so, do I simply turn the valet key and press the button at the same time? It's amazing how log it is taking for the car to charge via the 80 amp fuse. Oh yeah, the ignition off situation seems to be a better concept, yet I thought the battery electrical circuit was turned off via the 80 amp fuse if the ignition was turned off.


How long do you believe it will take to a) charge the battery and start the car, or b) use the key method to open the trunk, if the valet key will work?




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