Parasitic draw issue

1999 Toyota Tacoma. No frills,A/C,aftermarket radio,5 speed,crank windows.
There is a parasitic amp draw that is kicking my butt. Confirmed slight amp draw at the fuse panel. I've unhooked everything including the dome lamp but no success. Possible diode issue in the alternator? Can that be confirmed??

 

Its possible. If you read a draw a the fuse box, the question is what circuit is drawing amperage?

 

A Shorted positive diode will drain the battery with the key off. Disconnect the positive wire from the Alt and see if the drain is gone , making sure everything (And I mean EVERYTHING) is off and the doors are closed.

 

I guess "slight" is the question. Mine runs around 10mA and is normal.

 

Thanx for the replies! I had some questionable readings & my neighbor reconfirmed with a better meter,I work with AC voltage all day,and there is NOT a draw large enough to kill the battery every five days even though I only drive several miles a day to work this shouldn't be happening.
I will try the alternator check when I can.......

 

the slight amp draw could be your trucks keep alive memory for the ECU and radio.

and your battery dying could be from a bad cell. bad cells can't hold a charge for very long.

 

New battery. Radio unhooked,battery died in 3-4 days. 1999 four cylinder,shouldn't have much of an ECU? lol. And I would see a big draw at the ECU relay?
Think I'll roll the dice & change the alternator,it is 16 years old & lives in the desert.???

 

You can check this in 10min by unbolting the + from the alternator.

 

What am I looking for then Cal?

 

I asked you in the very first response. You said there is an amp draw at the fuse box. What circuit was it? Ill even attach the wiring schematic below.

If you think it is the alternator, you can remove the B+ from it and check again, its a large gauge white cable. Better yet, you can also use the diode function on your multimeter to check the rectifier. Here are instructions for that.

You can use the diode setting to check between the B+ and case housing. Swapping leads should give you a reading one way, and 0 another.

 

Another quick check for a leaking diode is that your alternator will be warm with a cold engine, but the best way is an inline current test in the B+ lead from the alternator.