electrical drain
Thread Starter
Safety Car
Joined: Nov 2008
Posts: 4,368
Likes: 9
From: Colorado
electrical drain
Car died last weekend after a 30 mile drive it wouldn't turn over after stopping for just a minute. I got a jump and drove it home but it wouldn't turn over after that. My charger has an alternator check function and it showed 25% so I replaced it. Auto parts store tested the battery and said it was fine. I kept it on a trickle charger and drove it yesterday, fortunately I was thinking ahead and when I turned it off I was at a parts store. Battery was dead so I got a new battery, (old battery tested dead). So I drove it tonight and while driving it all seems ok, got home and it wouldn't turn over
I'll check connections tomorrow but I just don't know what could be causing such a massive drain, assuming the alternator replacement is good
I'll check connections tomorrow but I just don't know what could be causing such a massive drain, assuming the alternator replacement is good
Melting Slicks
Joined: Apr 2009
Posts: 2,632
Likes: 112
From: Great Plains Iowa
Car died last weekend after a 30 mile drive it wouldn't turn over after stopping for just a minute. I got a jump and drove it home but it wouldn't turn over after that. My charger has an alternator check function and it showed 25% so I replaced it. Auto parts store tested the battery and said it was fine. I kept it on a trickle charger and drove it yesterday, fortunately I was thinking ahead and when I turned it off I was at a parts store. Battery was dead so I got a new battery, (old battery tested dead). So I drove it tonight and while driving it all seems ok, got home and it wouldn't turn over
I'll check connections tomorrow but I just don't know what could be causing such a massive drain, assuming the alternator replacement is good
I'll check connections tomorrow but I just don't know what could be causing such a massive drain, assuming the alternator replacement is good
Your problem could be something as simple and inexpensive as a bad engine ground cable. The OEM cables are made out of aluminum with aluminum eyes and after years of use the cables fail because of corrosion that has built up inside the eye. So I recommend replacing your engine ground cable with a good COPPER cable with COPPER eyes before you do anything else.
Thread Starter
Safety Car
Joined: Nov 2008
Posts: 4,368
Likes: 9
From: Colorado
I plan on checking that when I can. I know there was a lot of yanking on cables to get everything set up, battery tender, cut off switch, and battery so the ground could be tweaked. Thanks for the suggestion
Thread Starter
Safety Car
Joined: Nov 2008
Posts: 4,368
Likes: 9
From: Colorado
Dumb question, it's a side mount battery and I am not sure what's available for replacing the ground cable. If I can find cable, I can cut to length and add the "ring" on the frame side, not sure what to do for the battery side. Would just a terminal bolt through a ring work on the side mount? I won`'t even begin until this evening at the earliest but I can stop at a couple local parts stores on the way home.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
Dumb question, it's a side mount battery and I am not sure what's available for replacing the ground cable. If I can find cable, I can cut to length and add the "ring" on the frame side, not sure what to do for the battery side. Would just a terminal bolt through a ring work on the side mount? I won`'t even begin until this evening at the earliest but I can stop at a couple local parts stores on the way home.
When you wrote the battery was DEAD...how was this determined???? YES..it makes BIG difference.
What you are 'talking' about are the battery cables... what was offered as help is the ENGINE GROUND which has nothing to do with the cables attached to the battery. Your engine ground wire is a big cable that connects the the engine mount perch bracket on the right side and bolts to the right side of the engine down by the starter support bracket.
DID they check your charging circuit when you got the battery installed at the auto parts store????
DUB
Drifting
Joined: Jun 2005
Posts: 1,950
Likes: 498
From: Chino Hills CA
Sounds like you changed all the typical components. Perhaps you have a parasitic drain which discharges your battery overnight. With everything turned off, is there a small spark when you connect your battery cables. If so, you have a drain. You could also connect an ammeter in series between one of your battery cables and the battery. That would tell you what the drain is in amps. You could then disconnect things, or pull fuses one at a time, checking the ammeter until you trace down the problem.
Thread Starter
Safety Car
Joined: Nov 2008
Posts: 4,368
Likes: 9
From: Colorado
Sounds like you changed all the typical components. Perhaps you have a parasitic drain which discharges your battery overnight. With everything turned off, is there a small spark when you connect your battery cables. If so, you have a drain. You could also connect an ammeter in series between one of your battery cables and the battery. That would tell you what the drain is in amps. You could then disconnect things, or pull fuses one at a time, checking the ammeter until you trace down the problem.
Thread Starter
Safety Car
Joined: Nov 2008
Posts: 4,368
Likes: 9
From: Colorado
FIRST OFF...what YEAR is your Corvette????
When you wrote the battery was DEAD...how was this determined???? YES..it makes BIG difference.
What you are 'talking' about are the battery cables... what was offered as help is the ENGINE GROUND which has nothing to do with the cables attached to the battery. Your engine ground wire is a big cable that connects the the engine mount perch bracket on the right side and bolts to the right side of the engine down by the starter support bracket.
DID they check your charging circuit when you got the battery installed at the auto parts store????
DUB
When you wrote the battery was DEAD...how was this determined???? YES..it makes BIG difference.
What you are 'talking' about are the battery cables... what was offered as help is the ENGINE GROUND which has nothing to do with the cables attached to the battery. Your engine ground wire is a big cable that connects the the engine mount perch bracket on the right side and bolts to the right side of the engine down by the starter support bracket.
DID they check your charging circuit when you got the battery installed at the auto parts store????
DUB
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Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
I do not go by avatars when trying to figure out a year model...many members have more than one Corvette.
YES...you need to verify your charging circuit and how it works. PLEASE inform us on what you find.
DUB
YES...you need to verify your charging circuit and how it works. PLEASE inform us on what you find.
DUB
Thread Starter
Safety Car
Joined: Nov 2008
Posts: 4,368
Likes: 9
From: Colorado
Sounds like you changed all the typical components. Perhaps you have a parasitic drain which discharges your battery overnight. With everything turned off, is there a small spark when you connect your battery cables. If so, you have a drain. You could also connect an ammeter in series between one of your battery cables and the battery. That would tell you what the drain is in amps. You could then disconnect things, or pull fuses one at a time, checking the ammeter until you trace down the problem.
I'll get to the parasitic drain next, when I have time, thanks!
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
Seems to start, run, stop, restart like a champ! I had a heck of a time getting the battery tender ring terminal under the side post mount so ditched it for now. Seems it was a bad connection associated with that and or the cut off switch I ditched also. I'll get to the parasitic drain next, when I have time, thanks!
I'll get to the parasitic drain next, when I have time, thanks!I am curious what your charging circuit is doing...when ever you can get it checked out. Just remember the battery cable ends need to be CLEAN and the bolts TIGHT.
DUB
Thread Starter
Safety Car
Joined: Nov 2008
Posts: 4,368
Likes: 9
From: Colorado
Voltage running at idle 14.11 pretty steady when revved
Voltage with lights radio fan etc 13.98
Voltage engine off after prior tests 12.9
Leads not long enough to test for drop from alternator to battery, pos and neg sides.
My question now is how to I keep the door switch depressed for testing parasitic drain, tried a few things to wedge it down but nothing really worked.
Voltage with lights radio fan etc 13.98
Voltage engine off after prior tests 12.9
Leads not long enough to test for drop from alternator to battery, pos and neg sides.
My question now is how to I keep the door switch depressed for testing parasitic drain, tried a few things to wedge it down but nothing really worked.
Administrator
Joined: Jul 2000
Posts: 53,972
Likes: 6,197
From: About 1100 miles from where I call home.
In April I had the same trouble with my '69 after waking it up from winter. tested the alt, batt, etc. Checked the courtesy light switches in the jambs because sometime they stick in.
Turned out, my center console lid behind the seat was ajar, and apparently this caused the little light to stay on all the time, always causing my battery to be dead.
It might be something goofy like that.
Turned out, my center console lid behind the seat was ajar, and apparently this caused the little light to stay on all the time, always causing my battery to be dead.
It might be something goofy like that.
Instructor
Joined: Mar 2013
Posts: 205
Likes: 20
Me too! My center console lid was ajar and the battery drained very quickly.
Thread Starter
Safety Car
Joined: Nov 2008
Posts: 4,368
Likes: 9
From: Colorado
Detected a 2.1 Amp parasitic drain Pulled fuses and the clock/courtesy fuse removal dropped the current to zero so I found the circuit. Now I get to figure out what's causing it. The clock has never worked, the courtesy lights and timer seem to be working just fine. The alarm is associated with that circuit and I suspect that could be the culprit. It did trigger once while driving which was kind of embarrassing, but it stopped on its own (fried flasher?). Prior to that it did function but I avoided using it because I would trigger it while locking or unlocking more often than not. Do I go to the anti theft relay? Not sure what I am looking for at the moment.
Pulled fuses and the clock/courtesy fuse removal dropped the current to zero so I found the circuit. Now I get to figure out what's causing it. The clock has never worked, the courtesy lights and timer seem to be working just fine. The alarm is associated with that circuit and I suspect that could be the culprit. It did trigger once while driving which was kind of embarrassing, but it stopped on its own (fried flasher?). Prior to that it did function but I avoided using it because I would trigger it while locking or unlocking more often than not. Do I go to the anti theft relay? Not sure what I am looking for at the moment.
Race Director
Joined: Apr 2009
Posts: 19,294
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From: Charlotte NC
UN PLUG your timer controller for your courtesy lights. I have seen NUMEROUS times that the timer may work fine....BUT will still draw power...AND THE LIGHTS NOT BE SHINING!. SO pull the controller...put the fuse back in and see what happens. The plug it back in. You know...the process of elimination.
AS for the alarm system....I do not have my diagram her at home and I know that GM went to a theft module...but I can not remember exactly what year they started using it. If it was in 1979 or 1980.
DUB
AS for the alarm system....I do not have my diagram her at home and I know that GM went to a theft module...but I can not remember exactly what year they started using it. If it was in 1979 or 1980.
DUB
Thread Starter
Safety Car
Joined: Nov 2008
Posts: 4,368
Likes: 9
From: Colorado
UN PLUG your timer controller for your courtesy lights. I have seen NUMEROUS times that the timer may work fine....BUT will still draw power...AND THE LIGHTS NOT BE SHINING!. SO pull the controller...put the fuse back in and see what happens. The plug it back in. You know...the process of elimination.
AS for the alarm system....I do not have my diagram her at home and I know that GM went to a theft module...but I can not remember exactly what year they started using it. If it was in 1979 or 1980.
DUB
AS for the alarm system....I do not have my diagram her at home and I know that GM went to a theft module...but I can not remember exactly what year they started using it. If it was in 1979 or 1980.
DUB
it'll be awhile till I get to the timer, which I know is a frequent culprit. My 79 shop manual shows an "alarm relay" which is under the console next to the flasher. I also wonder about the door key switch and if it can cause the issue. Nice to know which circuit but getting to each component is a bit of a pita
Last edited by tonak; Jun 14, 2015 at 07:05 PM.
Thread Starter
Safety Car
Joined: Nov 2008
Posts: 4,368
Likes: 9
From: Colorado
it'll be awhile till I get to the timer, which I know is a frequent culprit. My 79 shop manual shows an "alarm relay" which is under the console next to the flasher. I also wonder about the door key switch and if it can cause the issue. Nice to know which circuit but getting to each component is a bit of a pita
Thinking that's good enough isn't it? Thanks for the directions DUB, now I still need to figure out the alarm system, but that can wait!!
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
AS for your alarm system....keep this in mind....your alarm system being the design with a flasher and a relay. ALL IT IS IS A NOISE MAKER!!!! AND it will continue to 'squawk' and drain your battery if it is not shut off. In 1980...GM changed the design to a controller that would shut down the horn and save the battery but still be active. I know there are many opinions on this subject...but to me....getting an outdated system working that has design faults/problems...is like trying to get an 8-track tape player working. Why waste the time. If anything...implement the newer design in the car. I have installed a VATS system form a C4 in a 1978 with an in-tank electric fuel pump and with the chip in the ignition key....I had it so the fuel pump and the starter would not work if all variables where not correct. And if someone 'hot wired' the car...it would only run as far as the fuel in the carburetor would allow it to go...which is about 5 feet (if that) and then die.
DUB
Heel & Toe
Joined: Oct 2008
Posts: 22
Likes: 1
From: Pittsburgh PA
In April I had the same trouble with my '69 after waking it up from winter. tested the alt, batt, etc. Checked the courtesy light switches in the jambs because sometime they stick in.
Turned out, my center console lid behind the seat was ajar, and apparently this caused the little light to stay on all the time, always causing my battery to be dead.
It might be something goofy like that.
Turned out, my center console lid behind the seat was ajar, and apparently this caused the little light to stay on all the time, always causing my battery to be dead.
It might be something goofy like that.
Thanks for the heads up - that was my problem too!!