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Good afternoon everybody. I am experiencing the old 'ghost draw' on my battery and am trying to track it down. I just tested the alternator by pulling off the + battery cable while the car was idling...kept on running with no problems. What would I look for at the starter solenoid relay, and/or voltage regulator to see if one of those is the culprit? All fuses are showing fine. The car itself is a 1966 base 289 2v with no A/C. The battery is brand new and tests well, but loses charge overnight. HELP!!!
 

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Legit, call me crazy I had this issue for a while and the problem ended up being a bad ground to one of my headlights. No idea why that would cause such and issue but once I saw the ground wire hanging and set it back up she's been starting right up! So check the grounds, or if you have an aftermarket stereo with an amp check that, had a friend set up his system wrong so the amp always stayed on and drained the battery. another thing to check is the alternator belt, make sure the alternator is adjusted right so that belt is tight and no slipping so it actually charges. Anyways hope that helps a bit, good luck!
 

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You need to start with a parasitic draw test. What is parasitic draw? All vehicles draw some power from the batteries when the car is shut off. Certain accessories such as clocks, radios and alarms always need power. The normal power used is called parasitic draw. It is always a very low draw so it doesn't run the battery down. If there is an electrical short in the vehicle or a malfunctioning accessory it could be drawing much more than its normal load causing a drain on the battery.



In order to check for parasitic draw, you need a DVOM (digital volt ohm meter)

  1. If you don't already have one, get a digital meter capable of reading 10amps or 20 amps
  2. Your battery must have a reasonable charge for this test to work.
  3. Check to make sure ALL loads are turned off. This is important so as to not blow your meter fuse or ruin your meter. Also make sure your meter is on either the 10 or 20 amp scale and not on milliamps. Unplug anything you may have plugged into the cigarette lighter. Remove your keys from the ignition. Close all doors so the dome lights are off.
  4. Disconnect the Negative Battery cable.
  5. To start make sure your meter is set to the 10 amp DC range. Some meters have a special connector for the red probe when you are reading current. If yours does, make sure the meter end of the probe is in the right connector. You can either do this next step by just holding the meter probes to their contact points or you can use probes with alligator clips to snap them in place so your hands are free.
  6. Connect the positive meter probe to the battery Negative post.
  7. Connect the negative meter probe to the disconnected battery cable.
  8. If everything is normal, you will read less than 35 milliamps, or .035 amps. If the current drain is higher than that, you need to find out what is draining your battery: You can start by pulling fuses until the load goes away. When the load goes away see what that circuit powers it might power several different items. So you can deduce from there by disconnecting the load device. IE: the dome light fuse may kill the draw and lets say when you pull the glove box bulb out and reinstall the fuse your draw is gone then the culprit is the glove box light probably bad switch. If pulling all fuses doesnt reduce the draw then you have a none fused draw. Look for devices that arent fused.
 

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I know iv said it before, but watch that pesky Glove Box light. If the button doesnt get pushed in all the way, the light will stay on.
 

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Discussion Starter #5
I will do a step by step using the info that you all provided. I will let you know that outcome when I rid my car of the gremlins! Have a great day everybody.
 

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My issue was a frayed (old) wire. Exposed wire touched metal and drained the battery causing the short described above. It was by luck I even found it.
Very frustrating. Good luck!!
 

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Discussion Starter #7
Finally tracked the problem back to the regulator and after replacing it, the pony is back on the streets with no sign of fatigue! Thx all.
 

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You need to start with a parasitic draw test. What is parasitic draw? All vehicles draw some power from the batteries when the car is shut off. Certain accessories such as clocks, radios and alarms always need power. The normal power used is called parasitic draw. It is always a very low draw so it doesn't run the battery down. If there is an electrical short in the vehicle or a malfunctioning accessory it could be drawing much more than its normal load causing a drain on the battery.



In order to check for parasitic draw, you need a DVOM (digital volt ohm meter)

  1. If you don't already have one, get a digital meter capable of reading 10amps or 20 amps
  2. Your battery must have a reasonable charge for this test to work.
  3. Check to make sure ALL loads are turned off. This is important so as to not blow your meter fuse or ruin your meter. Also make sure your meter is on either the 10 or 20 amp scale and not on milliamps. Unplug anything you may have plugged into the cigarette lighter. Remove your keys from the ignition. Close all doors so the dome lights are off.
  4. Disconnect the Negative Battery cable.
  5. To start make sure your meter is set to the 10 amp DC range. Some meters have a special connector for the red probe when you are reading current. If yours does, make sure the meter end of the probe is in the right connector. You can either do this next step by just holding the meter probes to their contact points or you can use probes with alligator clips to snap them in place so your hands are free.
  6. Connect the positive meter probe to the battery Negative post.
  7. Connect the negative meter probe to the disconnected battery cable.
  8. If everything is normal, you will read less than 35 milliamps, or .035 amps. If the current drain is higher than that, you need to find out what is draining your battery: You can start by pulling fuses until the load goes away. When the load goes away see what that circuit powers it might power several different items. So you can deduce from there by disconnecting the load device. IE: the dome light fuse may kill the draw and lets say when you pull the glove box bulb out and reinstall the fuse your draw is gone then the culprit is the glove box light probably bad switch. If pulling all fuses doesnt reduce the draw then you have a none fused draw. Look for devices that arent fused.
Like this. Detailed and complete. :)
 

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Another bad regulator

Just to chime in here, I also found my "ghost draw" to be a bad regulator. After chasing everything in the vehicle, pulling all fuses, etc... I pulled each lead of the VR and isolated the problem to it. Replaced the VR and all is well, I don't need to disconnect the battery cable overnight!
 
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