2003 WStar Battery drain

[bowtie_brain]

We bought our 03 Limited last Jan with 85,000 on it. Recently, it has developed a power drain while turned off. The battery and alternator have been checked, the battery is new as of Nov 08. We can jump start it and it runs fine, but after being parked for less than an hour, it won't crank. I have tried turning off the radio, power doors and dome lites with no success. I have checked the power ports for foreign materials (did ya ever get a penny stuck in one?). I pulled fuses 1 - 6 with a charger attached, watching the gauge for a dip when I pulled each one.
Any suggestions?

[rjeffreeze]

Sounds like a bum battery to me. Check out my recent post:
http://www.automotiveforums.com/vbul...d.php?t=932985
If you're still convinced it's not the battery, then you can check for current drain using Ford's TSB on the subject.

[Jeckler]

If the battery's negative terminal is disconnected for that same hour, then reconnected, it'll start?
BTW: An hour isn't a very long time. That's one hell of a drain if that's the case. You're talking every light in the car, including headlights.

[catvents]

Like Rjeffreeze, I would really suspect the battery, even if it is not very old. A load test of it would certainly comfirm if it is wrong. Not only a voltage test. ( all this according that your alternator is charging properly. (13.5 v.+)

[bowtie_brain]

Thanks. Load test on the batt, and on the alternator revealed that it exceeds the rating of the battery - 895 cca vs a rating of 850 cca. Charging system is at 14.14 V under load. I will check switches and amperage draw while shut down and see what I can find.
Tahnks for the input everyone.

[CnlK]

Think there was another post about the rear wiper drawing amps when vehicle was off. Personally I had a bad alternator that drew 4.5amps when vehicle was off. The brake on/off switches are also know to stick, you probably would have noticed the brakes lights on.

[Darrell T]

I have a 2001 wstar with a battery drain problem. i disconnected the positive cable from the battery, put a test light on the positive post and the alligator clip on the positive clamp. i then pulled each fuse one by one and the light never went out. i was told you could ceck your system this way - is this an accurate test or not? also disconnected alternator and starter and still had power at the light. the only time i could get the light to go out was by disconnecting the positive cable from main fuse box. should that main fuse box be "hot" when positive side is disconnected? Thanks for any suggestions...

[12Ounce]

Darrell T, you are on the right track ... Pull all the fuses, relays, and diodes ... ??? ... if you still have current draw, there is a leakage somewhere. But I bet you will not have to go that far.

[Darrell T]

to 12Ounce- i have tried all of that. every fuse, diodes and relays. the only time i get the test light to go out is when i disconnect the positive battery cable from the main fuse box. do you have any other ideas or suggestions?

[12Ounce]

Did you pull them "all together" ... or "one at a time"?

[Darrell T]

I tested them one at a time.

[12Ounce]

... pull them all together, and try again.

[Darrell T]

Pull ALL the fusses out at the same time? What will that tell me?

[12Ounce]

Pull them all ... test and observe ...
...and then reinstall one fuse or relay ... test and observe
... remove that fuse or relay, install another ... test and observe...
.... etc, etc.

Divide the problem.

[wiswind]

I only have access to the wiring diagram for my '96.
First thing that I want to say is that the pulling fuses one at a time, as you did, is a very good test.
The test has told you that the drain is NOT on those circuits.

I see the + power going straight to the alternator through "fusible links" A & B, these are not fuses, but are links

The + power also goes directly to the starter motor solenoid, no fuse, no fusible links.....a big red wire.
Power from the ignition switch, smaller Red with Light Blue Stripe wire, is supposed to pull in the "relay" contacts.
This wire passes through the Transmission Range Sensor (Neutral Safety Switch).

Do you have the Anti-Theft system?....That puts a "Starter Interrupt Relay) in line before the Transmission Range Sensor......activated by the antitheft control module.

I would try disconnecting the red wire from the Starter, and see if that makes any difference.

It looks like the ignition switch and headlights do not go through fuses.....so maybe disconnecting the healight switch at the dashboard?
There is a 20 amp circuit breaker INSIDE the headlight switch.