Okay, so I've been searching on line for a solution to 04 F-150 with parasidic battery draw.
Its not the battery. Its not the alternator. With ignition off I measure a 1.3-1.4 amp (yes amp not ma) draw on the battery that drains the battery overnight. I know this is a common problem as other have posted the same thing, but no one takes the time to post the solution. When disconnecting the radio fuse, the amps drop a bit but not enough.
How about the starter circuit do you have a multimeter do a voltage drop test on the starter. Or connect a meter to the battery and start removing fuses until you discover which circuit the draws on. That is a major draw. 4.6 or 5.4?
Grab a test light, disconnect a battery cable, put the test light in between the cable end and the battery post, if the test light turns on bright you have a draw that will kill a battery in no time, so start by electrically unplugging the alternator, if the light goes out then you have found you problem, replace the alternator, it has some bad diodes in it, if the light stays bright then start removing the fuses one at a time noting where each one came from until the light goes out, when that happens find out what is on that circuit, and repair or replace the offending component, then start replacing the fuses one at a time just to make sure the light stays out. Note: due to parasitic loads a test light might glow faintly, this is normal and will not kill a battery. HTH
With a draw like that it is not parasitic.
Have same problem 7.5 draw when truck is off checked fuse 23,25,40 23,25 draws 1.5 each 40 draws 3 all connected to low beam headlamps
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