Battery dead - Resolved 6/23/19

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juan214

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Battery dead after vehicles sit for a day or two. Jumps and runs fine, restarts fine then dead again after a day or two Battery is 45 days old or so. Put in a charged (backup) battery with a 12v plus charge. Did a parasitic test on vehicle. Disconnected the negative battery cable. Ran meter in series and set it on mA Base reading is steady at 04.63 mA. Remove each under hood and fuse box fuse and no change (even relays).

After 30 minutes sitting readings remained the same:
battery (backup) voltage at 12.08V
mA at 04.63
Alternator charging at 13.68V
Vehicle Battery 9.56V GAINED 1.52V while sitting disconnected for an hour while testing vehicle.

Any test or suggestions will be appreciated

Additional Notes:
Replaced the rebuilt one it had when purchased, it failed.
Replaced rebuilt alternator under warranty, it failed within a week or two.
Replacement rebuilt alternator installed
Alternator: currently charging @ 13.68V

Battery: current charge 8.04V
Replaced the one it had when purchased, it failed.
Replaced with used battery, it failed within warranty.
Replaced with used battery, it failed outside of warranty.
Replaced with new battery (12/18), it failed within warranty.
Replaced with new battery (5/19), current charge 8.04V.
Replacement installed

Starter: never change by us.

Not my truck...
 

stamp11127

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The one circuit that isn't protected by fuses is the alternator and it's output cable. If a diode shorts closed it will pull a battery down quickly.

Do the draw test again with the output cable disconnected.

Most mA draw should be in the 200-300 range with all the black boxes on vehicles today. Your reading is too low or the range changed and was missed. A 4 amp draw will pull a battery down rather quickly..

Forget the starter as your problem - it should only complete the circuit when the ignition key is turned to start.
 
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juan214

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Hey Rich,
Thanks for the reply. Happy Fathers day and give the pups a treat.

I thank you and everyone else on here as usual for all the help in advance. I give back when I can.

Auto electrical kills me, miss the old days. I let my son take the vehicle to work so there will be a delay in follow up.
  1. Did i do the tests wrong?
  2. The output cable is the charge cable at alternator correct?
When I do the draw test again with the output cable disconnected at alternator I'm doing the same test I complete above only with the cable disconnected at alternator to see if the reading at the battery changes?
 
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stamp11127

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Really can't say you did the tests wrong without seeing the meter display. The 4.63 mA is extremely low reading for today's vehicle but 463 mA is slightly less than 1/2 A. The test is the same as before, just not pulling fuses. Let the vehicle sit without turning anything on for about 15 minutes once you are set up. This will allow any modules to enter sleep mode and reduce power draw.

The alternator output cable is the single red cable that should have a rubber cover protecting it. Disconnect it once the battery has been disconnected to install the meter. Make sure it doesn't touch anything metal or things will get interesting quickly.

Hope you told him to disconnect the battery once he gets to work. If not you are deep cycling the battery - not good unless it is a deep cycle battery.
 

stamp11127

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I looked back over your readings in the first post.

Recommendation - don't try to start the engine if battery voltage falls below 11.0 volts. The starter is a constant draw motor that will pull any combination of voltage/amps needed to operate. That means as voltage drops amp draw increases which kills solenoids and batteries. It may even take out the motor brushes over time due to heat damage.
 
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juan214

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I'm bored and do not want to work on my truck. I'm going to drive to his job a get a couple of readings. See if my battery charged up, lost voltage and a draw test to double check the mAs.

I figured it was the charge cable you were talking about. Everyone likes fireworks it almost that time of year.

i gave him a 10 mm ratcheting open end wrench, I know he never disconnects if the battery ends up dead. If does connect it it's never tight. He leaves the headlights on all the time because the auto shut off. I keep telling him shut them off until we figure what is wrong with the charging system. Every time its dead they were on they only stay on for a few minutes but every volt counts when he's stuck somewhere. My battery is in and had 12.08 volts.

Thanks
 
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Plati

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You know for sure you don't have the rear wiper problem, right?
 

stamp11127

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Leave your son stuck at work for another 8 hours and he will learn the hard way to turn off the electrical loads.

Reminds me of when my son had to sit in the kiddie seat. He loved pushing the seat belt button which caused me to pull over and restrap the seat. One morning running late for dropping the 3 kids off at the daycare I hear the seat belt retract again. I told his sisters the next time he does that to hold on because we are going to stop quickly.
Not 5 minutes go by and snap. We were going about 45mph and I jump on the brakes, he is sitting in the middle of the back seat which pivots forward so that now he is looking down at the emergency brake handle between the two front seats.
"Darn Christopher, haven't I told you to quit releasing that seat belt...." After what seemed like forever to him, hanging there stuck in his seat & being lectured, I put him back and re-strapped the seat belt. He sure was a little red in the face afterwards. That ended the releasing the seat belt.

Millennials - can't be taught by talking to them, they have to experience it in order to learn it.
 
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juan214

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I looked back over your readings in the first post.

Recommendation - don't try to start the engine if battery voltage falls below 11.0 volts. The starter is a constant draw motor that will pull any combination of voltage/amps needed to operate. That means as voltage drops amp draw increases which kills solenoids and batteries. It may even take out the motor brushes over time due to heat damage.

Minute changes
Battery held its charge (+01)
mAs dropped to 4.54 (-.09)

IMG_3271.JPG IMG_3272.JPG IMG_3273.JPG
 
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