Assuming the excellence of rebuild, the behaviour is that of a confused Power Manager. After serious and invasive surgery, involving hardware substitution and replacement, and with the system battery out of the machine all the while, resetting the PMU is well-nigh essential. If you are confident of the charge in the system battery, give the reassembled machine at least five minutes on the AC adapter before resetting the PMU. If you are not confident of the battery's charge, let the Lombard stand on the charger for an hour or so before reset. If there is still no joy, back to standing on the AC adapter for several more hours before trying to reset.

If, after that, you cannot get startup, remove the main batteryand AC adapter, and let the PB stand for 30-or-so min. to reset the logic board (and deplete the backup battery). Then repeat the above with no main battery (only the AC adapter) in place. Given still no cogent response, you are left with the gruesome possibility of a hardware fault.

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