I have a 2006 XLT 4x4 with about 45k miles that I usually only drive a few times a week. Last week the battery was dead, so I charged it and checked for power drain. I haven't load tested the battery but the 13 month old battery is holding about a 12.6v charge after being disconnected (from the charger and the truck) for a week.

Fuse 21 is a 15 amp fuse that says cluster keep alive power - this is my vampire circuit. Last week I was getting .25 amps draw with nothing on. Today I'm getting about .35 amps with the door open and all the dome lights manually switched off. When I pull fuse 21, the draw goes to .05 amps, so something on that circuit is pulling the power. I hear a relay engage when I plug the fuse in, but I've removed all of the pluggable relays in the fuse box with no change.


Any ideas as to what is on that circuit that is causing problems? Does anyone have a wiring diagram to share for that circuit or the instrument cluster?

 

I know this is almost a year since your post, but did you ever find an answer?

 

I was told by a Ford tech that the shifter needed to be changed but i did not complete the repair. I still intermittently have the problem. If the truck was driven daily it would never show up it is such a slow drain.

 

I have a center shift console. It has been damaged, but only to the shift **** from an outraged teenager. I have not replaced due to the fact of a little engineering until the $450 to change. To my knowledge the only item for power is the brake safety and the OD button. I have come to the same conclusion as you did, 0.55A of daw, but i do not drive my truck except on weekends, so that means it will be dead after 4 days going on the math of the battery AH. Makes it hard to understand of what the Ford tech meant.

 

It might be the brake shift interlock.

 

Short or long term solution is to put a battery tender in the truck or disconnect the battery for the weeks storage.
You have more current draw than I do. I can typically make it weekend to weekend without a dead battery.

 

I was at the ford dealership and the tech told a woman her battery was only at 275 CCA and it should be at 550. He asked if she drove the car a lot, she told him about 50 miles a week. He said she needs to get out and take the vehicle on a long drive, to get the battery charged up. He said the battery can actually start to lose a charge when the vehicle isn't driven a lot.

 

Actually the right way to keep your battery in check is using a battery desulfator.

 

I get this too.. something draining my battery. So I've resort to just disconnecting it during the week since it's only driven on the weekends.. haven't had time to diagnose the drain issue.

 

Something almost everyone fails to understand:

YOU MUST WAIT 40 MINUTES AFTER TOUCHING ANYTHING BEFORE RECORDING YOUR CURRENT DRAW!!!!

Otherwise, you're still measuring the current pulled by the battery saver relay which, on an '04, is integrated into the cluster's electronics.


Simplified procedure (the manual's procedure is more complex):

Connect the meter between the negative post and the negative battery lead.
Set a timer for 40 minutes.
Walk away (or at least DON'T TOUCH ANYTHING).
Come back after the timer goes off and read the meter.

THAT is your current draw when the electronics go to sleep. An expected value is under 50 mA.