[fenway]

Have a 2000 4 runner put new battery in it next day battery dead . Nothing left on ? charged it up it starts then let it sit and somthing drains it ?? Light blinks on & off in radio. Alternator checked out fine. Never had a problem with it until sold it to friend had it for 3 month and this started.

 

[toyomoho]

There have been several TN posts on checking for parasitic drains on the battery. Place an amp meter between one of the battery cables and the battery and check for high current draw. Should around around 50 milliamps.

Typical areas are the trunk light (if the car has one), aftermarket alarm system, bad alternator causing a drain on the battery, dome light or stereo remote amp not turning off.

 

[fourwd1]

There have been several TN posts on checking for parasitic drains on the battery. Place an amp meter between one of the battery cables and the battery and check for high current draw. Should around around 50 milliamps.

Yes, I've answered several threads on this, check this forum and the 1st & 2nd gen truck forums.
Even tho your alt tested good, it could still be the problem.