RE: Battery drain overnight?
disconnect the negative battery cable and connect an ammeter between the post and the cable. DO NOT open the doors or tailgate, as this will blow the fuse in your meter. you should also disconnect the underhood light. The service manual will give you specs on the correct amount of current draw, but it should be less than maybe 700 milliamps once the computer has gone to sleep. even that number is high, but a vehicle with many electrical accesories that have memory will draw possibly that much current when the vehicle is off. If the draw is high, start pulling fuses one at a time until your draw goes away, then get a schematic for that circuit and start tracing.
disconnect the negative battery cable and connect an ammeter between the post and the cable. DO NOT open the doors or tailgate, as this will blow the fuse in your meter. you should also disconnect the underhood light. The service manual will give you specs on the correct amount of current draw, but it should be less than maybe 700 milliamps once the computer has gone to sleep. even that number is high, but a vehicle with many electrical accesories that have memory will draw possibly that much current when the vehicle is off. If the draw is high, start pulling fuses one at a time until your draw goes away, then get a schematic for that circuit and start tracing.