Hi all,
My neighbor's kids truck battery drains from full charge to "no start" in 1-2 days.
'99 Ford F-150 w/ 4.6L engine.

He has already.....
1) Replaced the Battery.
2) Replaced the GEM module.
3) Replaced the Turn Signal Relay.
He did all this before I looked at it....

I checked the following....
1) Truck off, doors closed, hood open... Amp meter shows 3.6 amp draw.
When 1st hooked up, shows 4.2 amps... after a while drops to 3.6.
2) To isolate the draw, we pulled fuses while checking current draw at
battery.
a) Under Dash fuse Panel. (Yes, with door closed) We remove fuse #15
"stop lamp switch, speed control, brake shift interlock, ABS, PCM,GEM,
RABS test connector". (Really... couldn't be more stuff?)
b)Under the hood is another fuse box (drivers side). We remove Fuse #103.
"Junction Block Battery Feed".
3) Not sure if this helps... found that if we remove the #15 fuse under the
dash with the door opens, all interior lights flash on/off at about 1 second
intervals... weird.
4) Again, another weird one... with the fuse #15 removed and door closed,
the "ABS" indicator and some other indicators and dash lights are staying
partially lit... not fully lit.
5) The only "aftermarket" stuff i can see is a dealer installed trailer brake system. Wiring looks professional and disconnecting it does not remove the amperage drain.

I'm hoping that one of you wizards will give me the "slam dunk"... if this happens, it must be that. Can I be so lucky?

And, yes. I have my own '06 F-150 that i absolutely love. 6-cyl., manual trans, stripped down without even power door locks... my kinda technology. lol.

Thanks in Advance,
Bill Nicholas

 

3 amps is a good draw . Have you disconnected the alternator ? Do that , and check your draw .

 

3 amps is considered huge in my thoughts. I would be looking for something under .1 amp with all off.

 

.02 is good . .04 is fair . much more ... issues .

 

When I posted " good draw " I meant that was a big draw . Not that 3 amps was good . Must be a southern thing... Good can be bad .. !

 

Oh... sorry. Thought you were serious.
i'm just an old backyard mechanic, trying to help a young man out. He spent about all his money on the truck and really cannot afford to take it in for repairs.

 

The experiments and fuse pulling so far did not get rid of the drain? If not, pull the wires off the alternator and see if the drain goes away.

 

When we remove #103 from the PCM or #15 in the fuse box the draw goes away. I just can't figure out what component under those two fuses is causing the drain.
I hope that helps to clarify the issue. Thank you guys again for the help. Quite stuck at this point.

 

Go back in the fuse box and pull the accessory delay relay, and see if the drain goes away. That's the relay that is controlled by the GEM module, and lets various things work after the key is turned off.