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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.
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?