Parasitic Drain?
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
I was using simply a test light to test for draws. The yellow wire made the courtesy lights go ape crap. They pulsated on and off until the timer kicked them off. The test light pulsated with the flashing of the courtesy lights.
It was quite freaky. The damn car has a ghost.
It was quite freaky. The damn car has a ghost.
It is also possible that you stilll have the factory alarm system intact. The facotry theft deterrant module should be in the compartment area behind the passernger seat
I have run into an aftermarket alarm going off when I messed with the battery cables and disconnected them...and when I reconnected them...the alarm went off and I had to disarm it with the key fob. What you are seeing with this pulsing might be normal.
I am not there to see what you have going on with added electrical stuff. But like I have written...your car siting for 24 hours and the battery is not dead...I am still not convinced that you have a significant drain...but with still not knowing what your actual numerical amp draw is on this system when fully connected...I can not say any more.
DUB
Last edited by DUB; Dec 3, 2016 at 06:28 PM.
Le Mans Master
Joined: Dec 2006
Posts: 8,837
Likes: 1,028
On an 81, I would start by removing the glove box liner and disconnect the courtesy timer and the visor vanity light. They are both on the right side. Notorious failures on 81.
The after market alarm is suspect as well.
Power seat switch stuck on. Feel the motors underneath for heat.
Power window switch stuck on.
Power door lock stuck on.
The after market alarm is suspect as well.
Power seat switch stuck on. Feel the motors underneath for heat.
Power window switch stuck on.
Power door lock stuck on.
Instructor
Joined: Aug 2016
Posts: 235
Likes: 28
From: Fort McMurray Alberta
SR,
Mate, you've got a lot of suggestions and whatnot that seem to be looking like a spider web. All of it is good and all of it is relative. However, what I was trying to do was to keep things very simple and without any frustrations that you might be having. We all know that electrical can be a serious PITA - we all have been there more than once.
The title of this thread is "Parasitic drain?" So what I suggested days ago, before pulling the battery, checking connectors, going through "finer" drain tests such as a number of amps being drawn etc was to just confirm that you had a drain.
The simple method with the test light would taken 30 seconds and days ago brother.
You just needed to confirm there was a drain (Test light would have done that) and THEN we could go into things more in depth but confirming first is key.
"In my real world experience" which is over three decades on all vehicles as my career not just Corvettes tells me 12VDC and AMPS are just that - general electrical principles that affect all cars/trucks.
Do you need to know OHMS law ? Not for this issue. Do you need to know the exact Ma draw with a meter ? Not right now and not for this. Do you need to go looking at connectors and electrical motors ? Not right now.
You need to confirm a draw to start with and you have done that ...essentially.
DUB is right about the aftermarket alarm. Disconnect it in entirety when performing this test. The pulsing you're speaking about is related to the alarm IMO.
Take it right out of the equation and see what you have regarding the test.
BTW, if you park your car for more than a couple weeks and it won't start - you have a drain. Your test light will tell you that and it will be illuminated but just not very bright.
It seems cavemanish with a cheap test light but you will get confirmation which is exactly what you are looking for in this thread.
PM if you want to bounce anything off of me and I'll try to help.
I'll step away from the thread now mate. Good luck !
Mate, you've got a lot of suggestions and whatnot that seem to be looking like a spider web. All of it is good and all of it is relative. However, what I was trying to do was to keep things very simple and without any frustrations that you might be having. We all know that electrical can be a serious PITA - we all have been there more than once.
The title of this thread is "Parasitic drain?" So what I suggested days ago, before pulling the battery, checking connectors, going through "finer" drain tests such as a number of amps being drawn etc was to just confirm that you had a drain.
The simple method with the test light would taken 30 seconds and days ago brother.
You just needed to confirm there was a drain (Test light would have done that) and THEN we could go into things more in depth but confirming first is key.
"In my real world experience" which is over three decades on all vehicles as my career not just Corvettes tells me 12VDC and AMPS are just that - general electrical principles that affect all cars/trucks.
Do you need to know OHMS law ? Not for this issue. Do you need to know the exact Ma draw with a meter ? Not right now and not for this. Do you need to go looking at connectors and electrical motors ? Not right now.
You need to confirm a draw to start with and you have done that ...essentially.
DUB is right about the aftermarket alarm. Disconnect it in entirety when performing this test. The pulsing you're speaking about is related to the alarm IMO.
Take it right out of the equation and see what you have regarding the test.
BTW, if you park your car for more than a couple weeks and it won't start - you have a drain. Your test light will tell you that and it will be illuminated but just not very bright.
It seems cavemanish with a cheap test light but you will get confirmation which is exactly what you are looking for in this thread.
PM if you want to bounce anything off of me and I'll try to help.
I'll step away from the thread now mate. Good luck !
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 5,339
Likes: 546
From: Central Texas
SR,
Mate, you've got a lot of suggestions and what not that seem to be looking like a spider web.
You just needed to confirm there was a drain (Test light would have done that) and THEN we could go into things more in depth but confirming first is key.
You need to confirm a draw to start with and you have done that ...essentially.
Mate, you've got a lot of suggestions and what not that seem to be looking like a spider web.
You just needed to confirm there was a drain (Test light would have done that) and THEN we could go into things more in depth but confirming first is key.
You need to confirm a draw to start with and you have done that ...essentially.
The battery is out of the equation now as it has been tested.
The alarm has issues no doubt. But is disconnected now as to not interfere with any other testing.
The battery has a fresh charge and has been reinstalled. I was planning on seeing if it would start this morning and then determine from there where to proceed.
Update - The car started with no problems cranking. Yellow wire disconnected. Radio dead. Everything else seems to be working except for disconnected alarm and radio.
Last edited by Street Rat; Dec 4, 2016 at 12:34 PM. Reason: add update
Burning Brakes
Joined: Jul 2016
Posts: 767
Likes: 74
From: Blaine MN
Yes a draw was confirmed with the test light. The offending wire has been disconnected at this point. I can find NO other draws on the battery at this time other than that wire.
The battery is out of the equation now as it has been tested.
The alarm has issues no doubt. But is disconnected now as to not interfere with any other testing.
The battery has a fresh charge and has been reinstalled. I was planning on seeing if it would start this morning and then determine from there where to proceed.
Update - The car started with no problems cranking. Yellow wire disconnected. Radio dead. Everything else seems to be working except for disconnected alarm and radio.
The battery is out of the equation now as it has been tested.
The alarm has issues no doubt. But is disconnected now as to not interfere with any other testing.
The battery has a fresh charge and has been reinstalled. I was planning on seeing if it would start this morning and then determine from there where to proceed.
Update - The car started with no problems cranking. Yellow wire disconnected. Radio dead. Everything else seems to be working except for disconnected alarm and radio.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
'Street Rat',
It seems that you are right back to POST#25.. Because in that post you wrote it sat for 24 hours and cranked right up. The only change is that you go the test light to go out on a circuit that you still do not know how many amps it is drawing.
Re-read paragraph 4 in POST #34. For whatever it may be worth.
The one COMMON thread in what I read that you wrote is that the car would not start AFTER you drove it and it sat for a short while. Once again..I do not think it is a drain because you would almost have to have your headlights on for 2 hours to get it to be hard to crank up.
And the other thing that is common in the two write-ups you did on how if it sat and would not crank after you just drove it is.... HEAT.
Thus....that connection I mentioned.
I hope it is fixed and does not come back to haunt you.
DUB
It seems that you are right back to POST#25.. Because in that post you wrote it sat for 24 hours and cranked right up. The only change is that you go the test light to go out on a circuit that you still do not know how many amps it is drawing.
Re-read paragraph 4 in POST #34. For whatever it may be worth.
The one COMMON thread in what I read that you wrote is that the car would not start AFTER you drove it and it sat for a short while. Once again..I do not think it is a drain because you would almost have to have your headlights on for 2 hours to get it to be hard to crank up.
And the other thing that is common in the two write-ups you did on how if it sat and would not crank after you just drove it is.... HEAT.
Thus....that connection I mentioned.
I hope it is fixed and does not come back to haunt you.
DUB
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 5,339
Likes: 546
From: Central Texas
DUB,
It is confirmed that the battery is good. The draw of the yellow wire is minimal. I find it hard to believe It can drain a battery down in two hours.
I don't believe that I have a parasitic drain now as long as the wire is disconnected.
So DUB I will check the amp drain on the yellow wire before connecting it again.
Now let's look at that connection to the starter that you mentioned. I have contact cleaner that I can clean the connections with. I also have some heat sleeve that I can wrap over the connection. What do you recommend? Any electrical testing at the connection?
The headers are wrapped with heat sleeve at the starter area below the starter.
It is confirmed that the battery is good. The draw of the yellow wire is minimal. I find it hard to believe It can drain a battery down in two hours.
I don't believe that I have a parasitic drain now as long as the wire is disconnected.
So DUB I will check the amp drain on the yellow wire before connecting it again.
Now let's look at that connection to the starter that you mentioned. I have contact cleaner that I can clean the connections with. I also have some heat sleeve that I can wrap over the connection. What do you recommend? Any electrical testing at the connection?
The headers are wrapped with heat sleeve at the starter area below the starter.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
DUB,
It is confirmed that the battery is good. The draw of the yellow wire is minimal. I find it hard to believe It can drain a battery down in two hours.
If what you wrote is correct...the yellow wire is NOT oyur problem....It simply can't be. Because you wrote that the car sat for 24 hours and cranked up...which is what I have been try to say.
I don't believe that I have a parasitic drain now as long as the wire is disconnected.
So DUB I will check the amp drain on the yellow wire before connecting it again.
Now let's look at that connection to the starter that you mentioned. I have contact cleaner that I can clean the connections with. I also have some heat sleeve that I can wrap over the connection. What do you recommend? Any electrical testing at the connection?
Did you separate this connection and actually perform a visual inspection of the terminals???
Contact cleaner will more than likely NOT do the trick. It may take a small wire wheel like you would use on a DREMEL tool and slowly brush the terminals to get them clean. THUS...they will need to be removed from the plastic connections....which is NOT hard to do. (If you need help in this: ASK)
Then once you get them removed and cleaned...you want to test fit them back to each other. Do one at a time. This way...you will be able to fell the 'drag' of the terminal when you connect them. You want them to be good and snug. NOT LOOSE and able to fall right out.
KEEP IN MIND.....this junction was something GM added for ease of assembly. Like I wrote in a past post. I often times join these wires together and will either solder them and use shrink wrap tubing...or cut off the terminals and solder them.....or solder them and do some modification so I can re-use the plastic connectors to make it still look facotry.
I can not think of any specific testing you need to do at this connection. Knowing that the car cranks (when cold) and everything works....I still feel this conenction is getting hot over time...and failing when you go to try to crank the car when HOT.
Even IF this is NOT your problem...this IS a problem area...nonetheless.
The headers are wrapped with heat sleeve at the starter area below the starter.
It is confirmed that the battery is good. The draw of the yellow wire is minimal. I find it hard to believe It can drain a battery down in two hours.
If what you wrote is correct...the yellow wire is NOT oyur problem....It simply can't be. Because you wrote that the car sat for 24 hours and cranked up...which is what I have been try to say.
I don't believe that I have a parasitic drain now as long as the wire is disconnected.
So DUB I will check the amp drain on the yellow wire before connecting it again.
Now let's look at that connection to the starter that you mentioned. I have contact cleaner that I can clean the connections with. I also have some heat sleeve that I can wrap over the connection. What do you recommend? Any electrical testing at the connection?
Did you separate this connection and actually perform a visual inspection of the terminals???
Contact cleaner will more than likely NOT do the trick. It may take a small wire wheel like you would use on a DREMEL tool and slowly brush the terminals to get them clean. THUS...they will need to be removed from the plastic connections....which is NOT hard to do. (If you need help in this: ASK)
Then once you get them removed and cleaned...you want to test fit them back to each other. Do one at a time. This way...you will be able to fell the 'drag' of the terminal when you connect them. You want them to be good and snug. NOT LOOSE and able to fall right out.
KEEP IN MIND.....this junction was something GM added for ease of assembly. Like I wrote in a past post. I often times join these wires together and will either solder them and use shrink wrap tubing...or cut off the terminals and solder them.....or solder them and do some modification so I can re-use the plastic connectors to make it still look facotry.
I can not think of any specific testing you need to do at this connection. Knowing that the car cranks (when cold) and everything works....I still feel this conenction is getting hot over time...and failing when you go to try to crank the car when HOT.
Even IF this is NOT your problem...this IS a problem area...nonetheless.
The headers are wrapped with heat sleeve at the starter area below the starter.
DUB
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Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 5,339
Likes: 546
From: Central Texas
The draw on the yellow wire was 40 ma. So I believe this is not the drain killing the battery. The alarm has several connections with 12+ constant power. For the time being I have disabled the alarm system.
I also pulled the starter harness connector apart. The male contacts seemed to pretty clean. I got a very small file and filed both sides of the male contacts. The file was thin enough to file the female contacts also. Sprayed the contacts with contact cleaner and reassembled the connector.
I did not pull the terminals out of the connectors.
So I will let the car sit a day or so without the battery tender connected and see if it starts up.
I also pulled the starter harness connector apart. The male contacts seemed to pretty clean. I got a very small file and filed both sides of the male contacts. The file was thin enough to file the female contacts also. Sprayed the contacts with contact cleaner and reassembled the connector.
I did not pull the terminals out of the connectors.
So I will let the car sit a day or so without the battery tender connected and see if it starts up.
Burning Brakes
Joined: Jul 2016
Posts: 767
Likes: 74
From: Blaine MN
The draw on the yellow wire was 40 ma. So I believe this is not the drain killing the battery. The alarm has several connections with 12+ constant power. For the time being I have disabled the alarm system.
I also pulled the starter harness connector apart. The male contacts seemed to pretty clean. I got a very small file and filed both sides of the male contacts. The file was thin enough to file the female contacts also. Sprayed the contacts with contact cleaner and reassembled the connector.
I did not pull the terminals out of the connectors.
So I will let the car sit a day or so without the battery tender connected and see if it starts up.
I also pulled the starter harness connector apart. The male contacts seemed to pretty clean. I got a very small file and filed both sides of the male contacts. The file was thin enough to file the female contacts also. Sprayed the contacts with contact cleaner and reassembled the connector.
I did not pull the terminals out of the connectors.
So I will let the car sit a day or so without the battery tender connected and see if it starts up.
Battery + Lug
Solenoid Start Terminal
Solenoid Bat Lug
Good luck, I really want to hear what your root cause ends up being.
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
I would be totally shocked if your car does not crank like it did for you after 24 hours...as you previosuly mrentioned..
I am glad that the connection I suggested you separated and cleaned. BUT...even IF it is clean and the plastic connectors are NOT burnt/melted. I remove each terminal and 'feel' how much resistance I feel when I join them together so I know I am having a good connection. This can not be done if you join it back together because you can not verify how snug these connections are when being joined...it is just guesswork.
AS you can see...there are some huge wires passing a lot of current though this connector. If you separate this connector...your cars ENTIRE electrical system is dead.....unless someone has modified it.
DUB
I am glad that the connection I suggested you separated and cleaned. BUT...even IF it is clean and the plastic connectors are NOT burnt/melted. I remove each terminal and 'feel' how much resistance I feel when I join them together so I know I am having a good connection. This can not be done if you join it back together because you can not verify how snug these connections are when being joined...it is just guesswork.
AS you can see...there are some huge wires passing a lot of current though this connector. If you separate this connector...your cars ENTIRE electrical system is dead.....unless someone has modified it.
DUB
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 5,339
Likes: 546
From: Central Texas
Car started this morning. I hooked up the yellow wire for the stereo memory. Tracked down the alarm wiring. I have been trying to get the alarm working for the past two days. It seems to work as it should now.
The big question is ...WHEN the car will do the non-start issue again?
The big question is ...WHEN the car will do the non-start issue again?
Race Director
Joined: Apr 2009
Posts: 19,294
Likes: 2,753
From: Charlotte NC
HEAT or TIME is your culprit...because it is doing it after you have driven it....and it is NOT a power drain.
So it is either heat is causing an electrical connection to fail...or time that that circuit is under a load and it being bad...causing the connection to fail.
I would have a volt meter and some wiring with me so I can check the key power circuits if it fails.
*** REAL LIFE EXPERIENCE***
Hopefully this may help those who read this.
I had a 1999 Corvette in my shop where on the information area of the dash...every possible warning was being displayed. 'Service ABS', 'Service traction control' and so on and on.
The car had a trouble code for the heated O2 sensor. In my testing I removed the fuse in the engine compartment fuse panel and checked to make sure I had 12 volts on one of the terminals for the fuse. I did.
When I installed the fuse....that terminal that WAS 12 volts was now dead....NO current at all. If I removed the fuse...the 12 volts came back. If I put it back in...the voltage died.
I KNEW what was going on...because I have been through a scenario like this before.
I grabbed the service manual and traced teh circuit right back to the ignition switch in the dash.
I removed the ignition switch and took it apart. SURE ENOUGH!!!! the contact in the ignition switch were burnt and messed up.
I installed a new ignition switch and NOT ONLY did the O2 sensor code go away....but ALL if the warnings in the information center did also.
This was simply due to the contacts INSIDE the ignition switch were making contact and you could read 12 volts on them....BUT....when the circuit(s) required a load on them....they failed.
DUB
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 5,339
Likes: 546
From: Central Texas
Update
Well I'm back to report that my inconsistent start issue has returned OR I have a new problem. Symptoms - Car doesn't start consistently. No matter hot or cold. Sitting for awhile or not. It's a roll of the dice each time that I get in the car. It clicks but doesn't start. Then it may or may not "catch" and start.
ANYWAY to make a long story short I think I found the issue today.
I was at a mechanic's house today.The car just happened to pull it's crap at the wrong house. After some diagnoses he got a hammer and banged on the starter while I cranked it. The damn thing turned right over.
Starter problem!
ANYWAY to make a long story short I think I found the issue today.
I was at a mechanic's house today.The car just happened to pull it's crap at the wrong house. After some diagnoses he got a hammer and banged on the starter while I cranked it. The damn thing turned right over.
Starter problem!
Thread Starter
Le Mans Master
Joined: Aug 2010
Posts: 5,339
Likes: 546
From: Central Texas
The Problem Has Been Found
Well I replaced the starter and that didn't fix it. 
To make a long story short, it ended up being the push together connector for the neutral safety switch.
I started another thread about how we found it. Here you go...
https://www.corvetteforum.com/forums...art-issue.html
To make a long story short, it ended up being the push together connector for the neutral safety switch.
I started another thread about how we found it. Here you go...
https://www.corvetteforum.com/forums...art-issue.html
Le Mans Master
Joined: Jan 2001
Posts: 6,713
Likes: 1,372
Just posting this for info..I recognize this is solved
I had a tough one previously where I had an intermittent amp draw due to a bad solenoid.
See post #5 in the below thread.
https://www.corvetteforum.com/forums...tic-drain.html
See post #5 in the below thread.
https://www.corvetteforum.com/forums...tic-drain.html