I've posted this on Bf.net as well but the more input the better.

I've booked my truck in to the auto electrician to find the source of my battery draining. It looses about a volt overnight. If left for 24hrs without driving it needs a jump to get going.
The sparky established that there is a drain & that the altenator is charging.

UPDATE:
The sparky's have had the truck for 2 days now but have not spent a lot of time on it due to overload of work.

They have finally narrowed the problem down to one of the big fuses in the engine compartment. The fuse is marked RAP. He did not know what this was so I looked in the owners manual & it is "Retained Accessory Power" so tomorrow he will investigate further.

Any further sugestions on what this feeds / what's hooked up to it would be appreciated. The info may shorten the time he needs to spend looking. (Tomorrow he intends to strip the dash!)

Possibly the central locking? Stereo? Security? What else would fall under Accessory?

Thanks guys!

 

if I remember correctly the engine Comp also falls under that?
its basicly anything that stays on with the key off

 

Yea. I should think so too. or the BCM itself?

Has ANYONE had issues in the past that may have involved this fuse???

 

The RAP fuse feeds the RAP relay which keeps power to the windows (including sunroof if equiped) and radio until any door is opened or the BCM times out.

To narrow down the source of the drain, pull the RDO IGN fuse and retest the draw. If that still shows a high draw, then remove the power window circuit breaker (metal rectangular item in the body relay block). On the LHD trucks, the body relay block is accessible off the end of the dash on the driver side. I am not sure where it is on your truck.

From there, if you do get it narrowed down to a particular system, you have to go to all of the components in that system and unplug them, testing each one at a time to narrow it down to a single component. I am betting that it is something with your radio causing the draw, but that would lead me to believe that the RAP relay is not being shut down by the BCM properly.

 

Thanks Kyle. I'll pass this info on. Hopefully this will get sorted soon.

 

4 DAYS & nearly 700 bucks later - Problem solved!

The lever on the seat to adjust the backrest was broken & pressing down on the switch which moves the seat back/forward!
I didn't realise this as my seat was usually always fully back but, come to think of it, it did seem to have moved forward sometimes & I had to move it back again.
(I am a bit sceptical on this as I'm not sure if the seats are wired thru the RAP fuse - unless it has something to do with the seats memory. I know with my Jeep, the seat moved right back when the key was removed from the ignition & moved back when put back in)

Anyway, once this was found, there was no trace of any drain on the system so whatever it was, isn't anymore. (fingers & toes X'd)

Now, about the seat lever...... I'll first check out what's already been discussed.

 

That is odd... Seats are always powered, not just through the RAP circuit... Glad you found the source of the drain though!

 

Thanks for the input Kyle. The only real damage was to my wallet! lol