H

hotjay18

Casual User
Feb 15, 2015
11
0
Awards
1
New-Brunswick
VetteCoins
300
Car
1978 Pace Car
Hey Guys!
I need some Electrical Genius up on here! My battery keeps going dead within a week. The battery itself is fine, keeps a charge on the bench if not in car. I have a 200mA draw on my battery. I tried removing every glass fuse underneath driver side dash, draw never goes away. Tried disconnecting alternator, draw still there. How do I fix this?

Help!!!!!
 
D

ddgermann

Power User
Jul 1, 2017
4,717
7,283
Awards
10
VetteCoins
477
Not sure about your Pace car but all C6s and C7s require a battery maintainer be plugged into the cars otherwise the computers will drain the battery in a short time.

Maybe your 8 track player is shorting out a bit... OK i'm just kidding. Parasitic draws are a bugger to find. GM dealers have a device they can plug in to help you narrow it down. I have had limited success with this on my H1 Hummer that had the same type of issue.

Basically it may come down to trial and error with a meter.

Maybe some other guys with C3s can give you a direction to start with.
For sure I would buy a battery maintainer and leave it plugged in in the meantime. Cheaper than replacing the battery. Hopefully you sort it out before it gets worse or becomes a short and dangerous.... although the circuits should be fused.

Good luck
 
  • Like
Reactions: Black 03 Z06
Black 03 Z06

Black 03 Z06

Staff member
Moderator
Power User
Oct 30, 2013
12,503
19,845
Awards
10
Haliburton, Ontario
VetteCoins
21,463
Car
2003 Z06
Province
ON
Wasn't there someone who recently joined the forum who was an automotive electrical expert? I remember making some crack about a toaster but cannot recall his name.

Anybody else remember.

OP good luck these electrical gremlins can drive you nuts. If you are in the garage can you shut off all light sources to see if there is a bulb glowing somewhere. Glove box, under hood, trunk light, licence plate bulb maybe the dash lights? Is there anything that does not function any longer but could still be drawing power?
 
  • Like
Reactions: ddgermann
nascar03

nascar03

Power User
Jan 27, 2009
3,898
3,613
Awards
10
Township of Langley, BC
VetteCoins
29,784
Car
1975 coupe/2003 vert
Province
BC
Good idea with the dark garage Murray..

hotjay... You do not have parstitic(?) loss..that is usually on the later computer controlled models, C4-C8.
Constant searching of modules and sensors causes battery drain.
On a C3-C1 you have a problem as almost everything shuts off when you remove the key, except if something is plugged into the ‘always live’ cigarette lighter.
Your idea of pulling fuses and disconnecting the alternator is sure the right place to start.
Has anyone ‘monkeyed’ with the wiring before you got this car(or since?)..
Add-on audio system?

Power seats. I don’t have those but they may be energized even with the key off?

If I think of anything else I’ll be back
Good luck.

Graham
 
Tony Gull

Tony Gull

Casual User
Nov 16, 2015
81
52
Awards
2
St. Albert
VetteCoins
849
Car
2018 Z06
A 200 milliamp draw may be a normal draw for that car. A bad battery only needs a small draw to make it dead quick and if this battery has gone completely dead even once then you'll probs need to change it. If you feel that the drain is the issue there is another way to investigate besides your method. Keep the meter on between the post and cable and unplug stuff like the wire to your distributor. I don't think you can cover all your circuits just by pulling fuses. Good luck.
 
A

Aramis76

Casual User
Feb 10, 2018
37
20
St-Colomban
VetteCoins
651
Car
Corvette 2017 Z51
I don't know the C3's at all, but if you've taken out all the fuses and it still drains, it could be a live wire somewhere that is on the main harness and over time has vibrated against the body/ground. That would suck because it means hunting a lot. Thankfully the C3 has less gadgets than later models so it should make this easier (a bit) to find.

One thing you can do, set an amp-meter to display that 200ma drain, and then wiggle some wires/cables. If it momentarily drops, you might be getting close.

Also, while your amp-meter is plugged in, disconnect the ECU, just to see if that drain could be coming from that. (assuming C3's have some sort of ECU, again, not familiar with them).
 
Keith Tedford

Keith Tedford

Power User
Apr 30, 2012
3,769
927
Awards
5
Ontario
VetteCoins
8,285
Car
2005 C6 1SB
With our 2005 six speed 1SB car, I put it in reverse, put on the emergency brake, shut the car off and never have a problem. I have a C-tek battery tender for winter storage. Had the car since 2012. The electrical systems in these cars are my one worry. Knock on wood that problems don't start for me. Fortunate so far.
 
  • Like
Reactions: Vetter81
wildone909

wildone909

Casual User
Aug 13, 2010
89
7
Awards
3
Port McNeill B.C
VetteCoins
317
Car
1980 , Red ,T.top
My 80 had a problem with the under hood light. The switch was stuck and the bulb was dead but still had a bit of a short.
 
Rruuff Day

Rruuff Day

Never wrestle with a pig.
Staff member
Moderator
Power User
Beta
Aug 30, 2014
11,766
13,851
Awards
11
Pine Lake, Alberta
VetteCoins
30,430
Car
C7 3LT ZF1
Province
AB
We had a big discussion on this around last November. Discussion also wrapped around failure or overcharge occurences with some tenders.I went to Costa Rica for 24 days in the winter and decided to unhook my battery tender, Then I forgot for a few days. Close as I can tell, Ginger went roughly 30 days without. Jumped in and it started right up... no sign of a weak battery... Go figure.
 
SlyMart

SlyMart

Regular
May 24, 2015
247
145
Awards
4
VetteCoins
766
Car
1978 Corvette
Maybe check the battery terminals. I think there is 3 of them since I removed mine. Maybe check your starter terminal connection? It could be a defective relay?
 
  • Like
Reactions: ddgermann
theboss

theboss

Regular
Nov 20, 2012
847
537
Awards
8
st-bruno, quebec, canada
VetteCoins
7,412
Car
2012 zr1 centennial
Province
QC
200MA for a car without plenty of module and computers seem hight to me. My next step would be to disconect the fuse link at the starter, they supply many circuit without passing true a fuse as the link is the fuse.
Stephane
 
  • Useful
Reactions: ddgermann
Keith Tedford

Keith Tedford

Power User
Apr 30, 2012
3,769
927
Awards
5
Ontario
VetteCoins
8,285
Car
2005 C6 1SB
I don't know about other years or why, but with our 2005 six speed standard, the manual specifically tells you to put the transmission in reverse and apply the emergency brake when shutting off the car. Never had a problem with battery drain but I do use a C-Tek battery maintainer/charger when storing the car. New battery in 2012 and never a problem.
 
  • Like
Reactions: ddgermann
L

lurch1313

I'm New Here
Jan 14, 2022
1
0
Awards
1
VetteCoins
12
Car
Corvette G.S. 2012
Province
USA
I have a 0.3 amp drain on my 2012 Corvette. Just so others won't waste their time, if you set the parking brake and then reverse, the start button lights flash and create a 5 amp draw. I waited 20 minutes to see if it would quit and it didn't. The FOBs were about 75' away when I tried it. I also canceled OnStar thinking they might be communicating with the car and that caused a drain. Pulled all the fuses and disconnected the alternator, no change. I have two large cables running off of the positive side of the battery and they both independently show the same 0.3 amp draw.
 

Similar threads

Users who are viewing this thread