Traceing down a .5 amp draw...
Thread Starter
Racer
Joined: Sep 2000
Posts: 291
Likes: 1
From: East TX
Traceing down a .5 amp draw...
Well, I figured out the steering column problem, and now wish to continue the original problem. If I leave the battery connected, it will go dead overnight. I put a amp meter between the disconnected positive battery cable, and the positive post on the battery, and read a .5 map draw. Is this the proper way to trace this? I've also pulled all the fuses and still have the same problem.... Any other ideas?
Race Director
Joined: Feb 1999
Posts: 12,772
Likes: 17
From: Indianapolis IN
Re: Traceing down a .5 amp draw... (david85)
On my 85 I had two wires touching on the power side of the the Fuel Pump Relay or the OD relay on the fire wall I dont recall which relay it was,
the connector wires are stripped back so far that they touched and would draw my battery down and make my lights DING if I ws driving and turned them on.
Sorry I cant help more but you could check them out.
the connector wires are stripped back so far that they touched and would draw my battery down and make my lights DING if I ws driving and turned them on.
Sorry I cant help more but you could check them out.
Team Owner
Joined: Dec 2000
Posts: 90,675
Likes: 304
From: SE NY
Cruise-In II Veteran
Re: Traceing down a .5 amp draw... (david85)
There are several fusable links from the battery but unfortunately my old '85 shop manual doesn't include the electrical suppliment volume.
While measuring leakage current, recheck that all lights are off and that the alarm system is not armed.
You may need to disconnect some of the fusable links from the terminal block behind the battery.
Try disconnecting the alternator, just for laughs & giggles.
While measuring leakage current, recheck that all lights are off and that the alarm system is not armed.
You may need to disconnect some of the fusable links from the terminal block behind the battery.
Try disconnecting the alternator, just for laughs & giggles.
Advanced
Joined: Oct 2003
Posts: 77
Likes: 0
From: Cave Creek AZ
Re: Traceing down a .5 amp draw... (david85)
This is a hassel because you have to get under the car. Disconnect the fat 12V line to the selenoid/starter. If your selenoid windings are going (shorted between turns) you'll start drawing current. You should be around 200/20 mA in awake/sleep mode. Just something to try. I just went through this.
Melting Slicks
Joined: Nov 2003
Posts: 3,375
Likes: 1
From: Northern CA
Re: Traceing down a .5 amp draw... (david85)
Sounds like a good approach to finding the problem. Did you possibly miss any fuses like the oddball ones hidden in the engine compartment?
Dick
Dick
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Every 2027 Corvette Engine Explained
Joe Kucinski
Designer Imagines A Corvette That Looks More Like a Corvette Than the Corvette
Verdad Gallardo
10 Ugly Corvettes That We Still Kinda Love
Joe Kucinski
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Instructor
Joined: Jan 2003
Posts: 102
Likes: 0
From: Carson City NV
Re: Traceing down a .5 amp draw... (85blkZ51)
You can easily determine the current draw for the glove compartment light and center console lights. Just turn each of these lights on separately and note what the current reading is. If it is close to .5amps you may have the culprit.
I have not experienced this, but someone posted recently that one of the car's computers can get "stuck" in an above normal current draw mode and will rapidly drain the battery. In their posting, they said that this "stuck" mode would stop if you disconnected the battery and then re-connected it. I suspect you have already tried this if you are already using your ammeter to troubleshoot.
20 milliamps is exactly what my 91 convertible draws after the courtesy lights go out and the security system goes into sleep mode.
The tip on disconnecting the alternator from the soup is a good one. If you have a diode going bad, it can drain the battery by allowing current to flow in the wrong direction. Be sure to let us know what you find. I am going to file that starter motor windings problem note above away for future reference!
I have not experienced this, but someone posted recently that one of the car's computers can get "stuck" in an above normal current draw mode and will rapidly drain the battery. In their posting, they said that this "stuck" mode would stop if you disconnected the battery and then re-connected it. I suspect you have already tried this if you are already using your ammeter to troubleshoot.
20 milliamps is exactly what my 91 convertible draws after the courtesy lights go out and the security system goes into sleep mode.
The tip on disconnecting the alternator from the soup is a good one. If you have a diode going bad, it can drain the battery by allowing current to flow in the wrong direction. Be sure to let us know what you find. I am going to file that starter motor windings problem note above away for future reference!
Thread Starter
Racer
Joined: Sep 2000
Posts: 291
Likes: 1
From: East TX
Re: Traceing down a .5 amp draw... (xs650)
Well, I tried the alternator with no help. Since buying the car, none of the interior/console lights have worked. It looks like my next try will be the fuseable links by the starter/firewall?
Team Owner
Joined: Mar 2001
Posts: 54,124
Likes: 30
From: Cincinnati, Oh USA
Re: Traceing down a .5 amp draw... (david85)
At night check for the underhood lights, the map compartment light, the courtesy lights, mirror lights, all external car lights. Do you have any electrical accessories? like a radar detector, aftermarket audio amplifier or radio ? Check em. Forum members have found seat adjust switches stuck on and start solenoid switches leaking current (remove the cable going to the starter after first disconnecting the positive battery cable). Good luck.
Melting Slicks
Joined: Nov 2003
Posts: 3,375
Likes: 1
From: Northern CA
Re: Traceing down a .5 amp draw... (jfb)
At night check for the underhood lights, .
Another way to check underhood and such lights is to open the hood while watching the ammeter. If the current doesn't increase, you know the light was already on.
Dick
Team Owner
Joined: Sep 2003
Posts: 20,179
Likes: 673
From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Re: Traceing down a .5 amp draw... (david85)
Not sure which circuit the vanity mirror and console light are on, you might want to check these.
:cheers:
:cheers:
Team Owner
Joined: Sep 2003
Posts: 20,179
Likes: 673
From: Freedom is never more than one generation away from extinction.
St. Jude '03 thru '24
Re: Traceing down a .5 amp draw... (david85)
Not sure which circuit the passenger's vanity mirror is on, you might want to check.
:cheers:
:cheers:
Burning Brakes
Joined: Jun 2003
Posts: 1,229
Likes: 1
Re: Traceing down a .5 amp draw... (69vetteracer)
I have an after market alarm system, the ones that make a lot of noise when you forget to disarm them before opening the door. :D
Anyway's my battery goes dead after about 2 weeks if I let the car sit without being started, I'm guessing this is because of my after market alarm system.
Just trying to give some ideas
good luck
Anyway's my battery goes dead after about 2 weeks if I let the car sit without being started, I'm guessing this is because of my after market alarm system.
Just trying to give some ideas
good luck