Mechanics

PHANTOM BATTERY DRAIN OR CHARGING CIRCUIT

2007 Ford Taurus • 90 miles

Charging light came on intermittently. For about two weeks. Seemed to come on spontaneously then go off with a braking movement. Then one morning it behaved as if the battery was dead. Starting solenoid clicking, etc.. Recharged it at an auto shop and an hour later a load test showed it was at 63%. Replaced the battery. Seemed to work fine for a day. The next day. I used the car and towards the end of the day the battery appeared to be low again. Funny clicking sounds for the instrument cluster, lights were dim, crazy warning signals come on and off; check breaks, air bag, etc. Turn signals weak, heating/cooling sys wouldn't come on. Then the engine died.

Haven't checked any fuses or the charging system. Could the battery be draining through a short? Or is it some tiny disconnect, split wire, connector, wiring harness, etc. That's behaving badly.
How do I dope it out. What and where should be checked next?
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Bobbyparagon
October 20, 2013.



Do you have a multi meter to do some testing?If so at idle see what the battery voltage at the battery is?Let me know what you find.

Saturntech9
Oct 20, 2013.
I went to start it this morning. It started. But after a minute. My air bag light went on. The the charging light went on. The instrument panel started clicking, other warning lights clinked on and off. Then the entire instrument panel went black. Rpm dial still indicating. Then the engine slowly went dead before I could put the meter on it. W/O engine running the VOM read about 11.60 V.

What should I check next.

We can do this : -)

Tiny
Bobbyparagon
Oct 20, 2013.
Charge the battery an start it up and see what the battery reads at the battery?Then we will check all the power inputs into the alternator.

Saturntech9
Oct 20, 2013.
OK. I charged the battery. Then promptly isolated it. I've found that as long as I charge and isolate it will RUN for a while about 15 minutes before it dies.

I check the in-circuit voltage before I started it this a.M. 12.4 Volts. When I started it and warmed up, with everything ON, A/C blower, lights, radio, etc. The voltage dropped to about 11.6.

I'm going to take it in to AutoZone for a diagnosis. Since I don't believe it's the battery which was installed three days ago.

I'll let you know what the diagnosis results are ASAP!

With your experience and my tenacity. WE can do this ! ! !

Tiny
Bobbyparagon
Oct 21, 2013.
Ran the diagnosis in car test at AutoZone. Battery checked out at 100% When charging test was attempted. Display indicated '" battery voltage too low to perform".

I suspect their something in the Alternator circuit, maybe the diode array is shot. AutoZone told me I'd have to pull the alternator to get it checked out. I will do that shortly. But isn't their a replacement diode array that can be plugged into the alternator?

What do you suggest?

With your experience and my tenacity. WE can do this ! ! !

Tiny
Bobbyparagon
Oct 21, 2013.
The diode will not cause too low of charging volts the regulator and the windings brushes etc will.I have been at my church all day doing maintaince as soon as I get home I will get you the voltage input checks to the alternator. Most likely a bad alternator that needs replaced.
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Saturntech9
Oct 21, 2013.
Alright with the key in the run position the orange wire with the yellow stripe should have battery voltage also the yellow wire with the white stripe should have artery voltage and the green wire with a yellow stripe should have battery voltage?

Saturntech9
Oct 21, 2013.
I pulled the alternator this afternoon. Will get it checked at AutoZone tomorrow a.M. Is it possible that the alternator operation was drawing current rather than producing it?

Didn't see any sign of burning, but it was clear for the wiring harness combing, etc. That it was thermally degrading but the car is 7 ears old. The connector plug wasn't burned however. If the alternator checks out OK. I'm really at a loss.

With your experience and my tenacity. WE can do this ! ! !

Tiny
Bobbyparagon
Oct 21, 2013.
Let me know how the alternator tests I gav you all the power inputs. The alternator isn't charging that's what I see is going on.

Saturntech9
Oct 22, 2013.
The alternator test results .

Lamp/Diode Trio PASSED

Rectifier PASSED

Regulator FAILED <

They didn't have one on the shelf, but they're getting one from their warehouse later today.

I'm putting it in TONIGHT!

Any advice. On the re-install?

Tiny
Bobbyparagon
Oct 22, 2013.
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