Toyota Repair: LandCruiser Battery Light flickering on/off, alternator failure, toyota repair

Question

The year is 1999, sorry!-------------------------------------------
The text above is a follow-up to ...

-----Question-----
My husband took his LandCruiser in to an authorized Toyota repair facility to see why the battery light was flickering.  They said the battery installed was a smaller one than should be.  They replaced it, and checked the alternator at that time.  It checked out okay.  Upon driving the car home, the light flicked on/off again.  Toyota said that it must be the alternator.  So, he brought it back in to have the alternator replaced.  $200 for battery replacement, $500 for alternator installed.  Upon picking up the car, the light came on AGAIN!!!  Did Toyota not follow procedure and should they have run a diagnosis on the light before suggesting these repairs?  And should they pay for these repairs that still have NOT fixed the problem?  It seems to me that they should be able to check the car's computer to troubleshoot the source of the problem.  Could it be something as simple as a short?  Please help!
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I need to know what year L/C it is before I can start to be of any help.

Answer
It's obvious that the dealer has misdiagnosed or not completely diagnosed the problem since you are still having the same problem,it would not be unreasonable for you to either ask for a refund of the repairs you paid for or at least ask them to find out what the real problem is without any further diagnostic expense to you, maybe the battery was the wrong size and maybe the alternator tested bad or maybe they guessed, I have no idea, the bottom line is that you paid a lot of money and the problem is still there.  I would suggest contacting the service manager and express your concern.   It's really hard for me to say what the problem may be since I do not have access to the vehicle, it may be a wiring problem, usually the battery light being on or flashing indicates an alternator failure but it doesn't seem to be the case here, there is another problem, the charging system is not computer controlled so there is no computer to troubleshoot, the alternator output is internally regulated, the charging system consists of the alternator, the battery and the wiring, that's all, so the the problem is within those three items, two of them have already been eliminated as the cause.