2009 Ranger XL battery drain

[ghunt81]

I have a 2009 Ranger XL that I've owned for about a year. I got it from an auction and it had a dead battery when I picked it up, which I just figured was from it sitting. I took it home and did a bunch of work to it over last summer, then drove it for the winter.

After spring rolled around I got my Mustang out and parked the Ranger in the garage. The Ranger sat for a couple weeks, and the next time I went to start it move it the battery was 100% dead, like it wasn't even lighting the dome light. Since then I have found that if I leave the battery hooked up and it's not being driven, it will draw it dead in about a week, maybe a little less.

Now, this is an XL, so it has almost no electrical accessories- lights, AM/FM radio, and that's about it, so I can't think of what would be drawing the battery like it is. Is anything known for drawing off the battery like this, where should I look?

 

[RonD]

2009 ranger will have Smart Junction Box(SJB) instead of GEM(generic electronic control module)

SJB is located behind Passenger side kick panel

Back in 1995/6 Rangers got a Battery Saver Relay circuit, it would cut power to cab electrics after about 20 min. of key off, it was controlled by timer in GEM and now SJB.

Go here: http://www.fleet.ford.com/partsandservice/owner-manuals/

To get 2009 Ranger manual
That should give you fuse locations, SJB is also cab fuse panel, and maybe the location of Battery Saver Relay.
Relay could be stuck ON, so power is not being cut after 20-30 min. this would be a slow drain but enough to kill battery after a week or so.

Because of the Battery Saver circuit it makes it harder to track down a drain.

Best method is to open hood and disable hood light, if it has one, remove Battery negative cable, use jumper cable to connect it back up, and then an AMP meter from cable to Battery.
You are going to disconnect jumper cable and leave AMP meter hooked up so set it up accordingly.
You need the jumper cable to handle the higher AMPs when key is on.
Roll down drivers window and close door, turn on key then turn it off and remove it.

Remove one end of jumper cable, AMP Meter should show just under 1 amp, 0.7 or so
Wait 20-30 min. if battery saver is working amps should drop to 0.03-0.07, this is expected drain from radio and "awake" circuit in SJB or keyless entry

 

[ghunt81]

If it matters, as far as I know the "battery saver" is working. I put new weatherstripping in the driver's door last year so the door has to be shut fairly hard to shut all the way. I have accidentally left it overnight with the door not completely shut, and noticed the cab light would be out when I went out to the truck, but if I shut the door completely and reopened it, it would come back on and the battery would not be dead.

I will have to try your testing method at some point, I just can't think of what could be draining the battery as it's evidently a pretty slow drain.

 

[RonD]

Well if you know it isn't on the Battery Saver circuit then you can just have everything off with hood open and passenger door open.
Have AMP Meter hooked up between battery negative cable and battery, then pull 1 fuse at a time, watch for small drop in amps.
Should be about 1 amp, with door open since battery saver relay hasn't shut off yet.
But what ever it is it will drop when draining circuit fuse is pulled.
Pulling Battery Saver fuse will cause it to drop alot, and you can leave it out if you want.

You are shooting for 0.03-0.07 that is spec