Ford Repair: F150 Battery Drain, fuse box, diagnostic tips


Question
Current Drain Fuse#11

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2001 F150SC 4.6L 2WD MT
Hi,
Having a dead (very weak) battery for a few days (1 week old new battery and 2week old alternator) I gave the vehicle to the local guy who could not detect a current draw. I got the battery replaced by was not convinced that was the root cause. I followed some of the diagnostic tips on the other threads to troubleshoot my current draw issue on my battery. Here is how I proceeded:
Conditions Outside Temp ~10F
Start engine, wait till cluster lights go out, turn headlights on then off, bypass neg terminal with wire while engine running while carefully sliding loosened neg battery cable from battery. Enter vehicle, shut off headlamps and remove key then exit truck and close door and lock with key FOB (one click). Verify all internal/exterior lights are off.

This is the Normal Sequence I observed for two of the starting cycles:
Initial Amperage after locking when using FOB: ~1.75A for several seconds,
then 210mA another 0.5 -1 hour
then 12mA for the duration

After two of these 'Normal? cycles I saw a 2.75A draw almost immediately that lasted over a half hour. Thinking I had finally caught the 'gremlin', I started pulling fuses from the underhood fuse box. When I got to fuse#11 (Alternator Field) the current immediately dropped to 210mA and remained there for ~15minutes then dropped to 12mA where it remained. I also should have added that I replaced the #11 fuse immediately but did not see any amperage fluctuations so I left it in. Any Ideas?

Answer
once you had 11 fuse out and reinstalled it you had already killed alt field so it would not come back probably until energized again-i am not very good at walking people through parasitic drains-i see nothing wrong with your procedure it is just aggravating to find a draw at times
especially if intermittent i would have to be there to help much with this, sorry but i would be suspicious of that alternator.