Land Rover Repair: gearbox fault\loss of power in gas pedal, fault message, interstate battery

Question
MY truck wouldn't start at first then it started and I drove about 2 blocks and it quit now it says gearbox fault in the message center and I have loss of power in my engine because when I press the gas pedal my truck doesn't automatically go there is build up then it moves ,and with noticebly less power I would like to fix this myself if possible considering I have spent alot of money already on the love of my life (my truck)and I know I won't be able to spend much more or my wife will force me to get something else( through the POWER of Nagging)

Answer
Hi Robert,

The failure to start and the "gearbox fault" message are both signs of a dying battery, loss of power may be a result of the battery as well because of loss of power to the ECU but I can't say for certain.  Have your battery tested, if it's bad replace with an Interstate battery (they have the OEM spec. battery).  Ensure it's the right one for your LR, a too small battery will not last and will cause issues (possibly what your're seeing now).  You may have charging issues with your alternator, but start with the battery.