1970 Battery Drain
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Intermediate
Joined: Feb 2016
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1970 Battery Drain
Battery is draining after 4-5 days.
I have searched this topic and have already checked the easy...
- Battery is new
- With car running battery is 14.47v and check at alternator is 14.51v
- Removed neg cable and check with multi-meter in series, it shows 0.08 amps
This seems low to be draining? Thoughts on next step(s)?
It does have an alarm(not sure if everything is hooked up), no power windows. The horn works intermittently, have to press it a few times.
Thx
Shawn
I have searched this topic and have already checked the easy...
- Battery is new
- With car running battery is 14.47v and check at alternator is 14.51v
- Removed neg cable and check with multi-meter in series, it shows 0.08 amps
This seems low to be draining? Thoughts on next step(s)?
It does have an alarm(not sure if everything is hooked up), no power windows. The horn works intermittently, have to press it a few times.
Thx
Shawn
Team Owner
Joined: Jul 2006
Posts: 22,167
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From: Kannapolis NC
That's not a terrible drain. First check the common stuff. Are any lights staying on? Courtesy, storage compartment, rear? Is your radio stock or aftermarket? Is the clock running?
I think if it's draining in a few days with only .08 amps, I'd run by one of the parts stores and have them run a test on the battery.
I think if it's draining in a few days with only .08 amps, I'd run by one of the parts stores and have them run a test on the battery.
Thread Starter
Intermediate
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after market radio. I just replaced the battery. Driver's door light switch is bad I know, have to pull it out for the courtesy lights to come on. No lights are on with the doors closed and battery hooked up.
Burning Brakes
Joined: Oct 2015
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Identify which fuse is for the alarm system..Probably same one as the interior lights..
Check owner's manual on how to activate and DEACTIVATE THE FACTORY ALARM..
Quite possibly the components in the alarm system are not working but still drawing current IF system is in the activated mode.
Pulling the proper fuse for the alarm circuitry and then measuring the parasitic current draw will show IF the alarm circuitry-components are the bugaboo..
Not sure if my '78 alarm or fuse panel is the same as your 70 so you just have to run thru some fairly simple tests to isolate the issue.
With car completely off only current draw should be the electric clock..unless alarm is ON..or THINKS it is ON.... point 8 amps will draw down a good battery in 3 days.. fact that the old battery acted the same is indicative of some parasitic current draw beyond the electric clock..Make sure your radio is truly off with car completely off..jim
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Drifting
Joined: Oct 2005
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From: Forth Worth TX
Pull one fuse at a time and see when the battery stops draining. Then use your wiring diagram and see what components are associated with that fuse and continue trouble shooting from there.
Last edited by Revi; Apr 11, 2016 at 12:02 PM.
Team Owner
Joined: Jul 2006
Posts: 22,167
Likes: 4,172
From: Kannapolis NC
Check the owner's manual for fuse panel/which fuses on what components..
Identify which fuse is for the alarm system..Probably same one as the interior lights..
Check owner's manual on how to activate and DEACTIVATE THE FACTORY ALARM..
Quite possibly the components in the alarm system are not working but still drawing current IF system is in the activated mode.
Pulling the proper fuse for the alarm circuitry and then measuring the parasitic current draw will show IF the alarm circuitry-components are the bugaboo..
Not sure if my '78 alarm or fuse panel is the same as your 70 so you just have to run thru some fairly simple tests to isolate the issue.
With car completely off only current draw should be the electric clock..unless alarm is ON..or THINKS it is ON.... point 8 amps will draw down a good battery in 3 days.. fact that the old battery acted the same is indicative of some parasitic current draw beyond the electric clock..Make sure your radio is truly off with car completely off..jim
Identify which fuse is for the alarm system..Probably same one as the interior lights..
Check owner's manual on how to activate and DEACTIVATE THE FACTORY ALARM..
Quite possibly the components in the alarm system are not working but still drawing current IF system is in the activated mode.
Pulling the proper fuse for the alarm circuitry and then measuring the parasitic current draw will show IF the alarm circuitry-components are the bugaboo..
Not sure if my '78 alarm or fuse panel is the same as your 70 so you just have to run thru some fairly simple tests to isolate the issue.
With car completely off only current draw should be the electric clock..unless alarm is ON..or THINKS it is ON.... point 8 amps will draw down a good battery in 3 days.. fact that the old battery acted the same is indicative of some parasitic current draw beyond the electric clock..Make sure your radio is truly off with car completely off..jim
An aftermarket radio with memory and clock will draw some current. Disconnect it or pull the fuse and check your drain again. Naturally the closer to zero the better. I'd pull the fuse for the clock and radio and check, then put one at a time back.
Team Owner
Joined: Jul 2006
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From: Kannapolis NC
You probably shouldn't worry about a light staying on, that would draw a lot more than .08, unless it's a backlight or something for your aftermarket radio. That's where I would start, with the radio.
If that's not it, I'd pull the plug off the alternator while monitoring draw, if it goes down you may have a leaky diode in the rectifier circuit in the alternator.
If that's not it, I'd pull the plug off the alternator while monitoring draw, if it goes down you may have a leaky diode in the rectifier circuit in the alternator.
Last edited by 65GGvert; Apr 11, 2016 at 02:31 PM.
Team Owner
Joined: Jul 2006
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From: Kannapolis NC
I disagree with a few days, but doesn't matter. He still needs to find if something is bad, or if that's what his radio and clock are drawing and make a decision. 80 thousandths of an amp will take a while to run down a charged battery. If 40 lasts a month, 80 should last 2 weeks.
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Removed radio fuse, draw is now .070(70 milliamps). So radio takes 10.
Noticed 2 purple wires left/front of fuse box that seemed to have lost wire-nut. I forgot to mention it has electric antenna as well.
Noticed 2 purple wires left/front of fuse box that seemed to have lost wire-nut. I forgot to mention it has electric antenna as well.
Team Owner
Joined: Jul 2006
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From: Kannapolis NC
That's pretty normal on a radio if it has station memory and a clock. Try the alternator plug and see what happens.
Team Owner
Joined: Jul 2006
Posts: 22,167
Likes: 4,172
From: Kannapolis NC