Car won't start! (electrical drain)
Thread Starter
Racer
Joined: May 2006
Posts: 415
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From: Dallas TX
Car won't start! (electrical drain)
So here's the situation, the low beam headlights wouldnt turn on but the highbeams worked. I found the problem was a burnt out/melted relay and also the positive wires coming from it was touching each other and burnt the plastic. I fixed this and thought that since that was the problem maybe it was causing a drain on the battery therefore the car would never start unless I jumped it. Headlights are now fixed but Im experiencing the exact same problem with the electrical leak somewhere. Battery takes a dive from 12.8 volts to under 10 in a matter of minutes. Car cant sit over night and be expected to start in the morning. The autoparts store checked the battery and alternator itself and deemed them ok.
I attempted to connect a volt/multimeter to the battery and pulling each fuse one by one to see if the electricity reading spikes at all, pointing to a problem in a Specific Circuit...with no luck yet.
This has been an absolute nightmare to own a car I cannot drive anywhere. Any help would be spectacular.
I attempted to connect a volt/multimeter to the battery and pulling each fuse one by one to see if the electricity reading spikes at all, pointing to a problem in a Specific Circuit...with no luck yet.
This has been an absolute nightmare to own a car I cannot drive anywhere. Any help would be spectacular.
Racer
Joined: Jun 2003
Posts: 256
Likes: 0
From: Newport Beach Ca
"Battery takes a dive from 12.8 volts to under 10 in a matter of minutes."
I assume that your measuring this voltage with a meter at the battery terminals? This statement would cause me to look harder at the battery. A current draw large enough to cause this voltage decay should be really obvious. It would be helpful if you could measure the current draw with the car at rest and everything shut off including the under hood light. Normal draw is in the range of 20 milliamps with everything off -----
Assuming no large current draw, it almost has to be a bad battery.
I assume that your measuring this voltage with a meter at the battery terminals? This statement would cause me to look harder at the battery. A current draw large enough to cause this voltage decay should be really obvious. It would be helpful if you could measure the current draw with the car at rest and everything shut off including the under hood light. Normal draw is in the range of 20 milliamps with everything off -----
Assuming no large current draw, it almost has to be a bad battery.
Race Director
Joined: May 2005
Posts: 15,960
Likes: 21
From: West Norriton PA
St. Jude Donor '08
So here's the situation, the low beam headlights wouldnt turn on but the highbeams worked. I found the problem was a burnt out/melted relay and also the positive wires coming from it was touching each other and burnt the plastic. I fixed this and thought that since that was the problem maybe it was causing a drain on the battery therefore the car would never start unless I jumped it. Headlights are now fixed but Im experiencing the exact same problem with the electrical leak somewhere. Battery takes a dive from 12.8 volts to under 10 in a matter of minutes. Car cant sit over night and be expected to start in the morning. The autoparts store checked the battery and alternator itself and deemed them ok.
I attempted to connect a volt/multimeter to the battery and pulling each fuse one by one to see if the electricity reading spikes at all, pointing to a problem in a Specific Circuit...with no luck yet.
This has been an absolute nightmare to own a car I cannot drive anywhere. Any help would be spectacular.
I attempted to connect a volt/multimeter to the battery and pulling each fuse one by one to see if the electricity reading spikes at all, pointing to a problem in a Specific Circuit...with no luck yet.
This has been an absolute nightmare to own a car I cannot drive anywhere. Any help would be spectacular.
Not sure what you are trying to say ???
When the car is running what kind of voltage are you seeing ?? 13.5 V
With the ignition off you should not see any voltage on your dash gauges.
The problem if it is ocurring when your ignition is off, is from a circuit that is either always on or hot when the ignition is off like your light circuit.
Check fuses in passenger footwell. Also check to see if your lights are off even though they are not in the on position as you could have a damaged multifuntion stalk switch from when you shorted out wires from the previous problem.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
"Battery takes a dive from 12.8 volts to under 10 in a matter of minutes."
I assume that your measuring this voltage with a meter at the battery terminals? This statement would cause me to look harder at the battery. A current draw large enough to cause this voltage decay should be really obvious. It would be helpful if you could measure the current draw with the car at rest and everything shut off including the under hood light. Normal draw is in the range of 20 milliamps with everything off -----
Assuming no large current draw, it almost has to be a bad battery.
I assume that your measuring this voltage with a meter at the battery terminals? This statement would cause me to look harder at the battery. A current draw large enough to cause this voltage decay should be really obvious. It would be helpful if you could measure the current draw with the car at rest and everything shut off including the under hood light. Normal draw is in the range of 20 milliamps with everything off -----
Assuming no large current draw, it almost has to be a bad battery.
For something to draw the battery down to 10 VDC in minutes would have to be smoking HOT!
Take your battery to another reputable automotive shop and ask them to load check the battery. That test will allow you to test the batteries ability to supply current and keep the voltage at the correct levels for the correct period of time. they will apply something like a 200 amp load on the battery for XX time. They have a chart that tells them what the battery output voltage should be. Your battery should be able to maintain 11.5- 12 vdc for quite a while. When you reconnect the battery, make sure the battery terminals are clean and tight. They require 11 FT/LBS of TQ to connect correctly.
My money is on a bad battery!
You cant pull fuses and see if the voltage drops off on a C5. There are PCM, BCM and security circuits drawing current/voltage all the time. As Bruceatlam stated, they only draw 20ma at 12 vdc which with a fully charged properly working battery will allow the car to sit for MONTHS with out a starting issue!
BC
Thread Starter
Racer
Joined: May 2006
Posts: 415
Likes: 0
From: Dallas TX
Yes I'm referring to the voltage reading in the DIC. To tell you the truth I dont know how to use this, When its on the battery terminals its reading about 100 set on DCV 150 that is with every off door closed.
Can I take the battery out of the car and bring it in for a load test and charge?
Can I take the battery out of the car and bring it in for a load test and charge?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Thats the WORST POS meter I have ever seen! 
I would invest in a better meter that makes sense.
Yes you can take the battery out of the car. Make sure the radio isn't LOCKED with a security code!
Disconnect the negative terminal first then the POSITIVE cable. Then remove the battery.
BC
I would invest in a better meter that makes sense. Yes you can take the battery out of the car. Make sure the radio isn't LOCKED with a security code!
Disconnect the negative terminal first then the POSITIVE cable. Then remove the battery.BC
Thread Starter
Racer
Joined: May 2006
Posts: 415
Likes: 0
From: Dallas TX
Alright so I took the battery out of the car and to the auto store they checked it again said it was okay but was showing 50% power so they put it on a charger for an hour, I put it back in the car and its been working so far but showing 11.9 volts when I get into the car. I remember seeing 12.2 the previous night when pulling the keys from the ignition. 
Thanks for your help, dont know if this battery is shot yet..
Thanks for your help, dont know if this battery is shot yet..
Last edited by Tuk; Sep 9, 2007 at 06:26 PM.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
If a battery is weak or defective, it will loose it's ability to hold a charge or will drop voltage quickly when under a load. Batteries can even short inside and kill them selves without even being connected to the car.
The only way that you can determine the health of a battery is to fully charge it and load test it. Shops worth going to will have the correct equipment to correctly test the battery correctly. They will also know how a C5 charging system works and will be able to correctly test the alternator output.
As for the car, the only way to figure out if theres a current draw problem is to do a current draw test. You can put brand new batteries in the car daily. If theres excessive current draw, there going to discharge the battery as it sits. My 02 ZO6 will sit for 2+ months and not have a starting issue. My 98 Coupe was the same. If you cant let the car sit for a short period of time without the battery discharging, you have some sort of problem.
On almost all C5's the actual battery voltage and or charging system voltage will be slightly lower on the interior dash gage and on the DIC than it is at the actual battery terminals. Make sure you compare the voltage in all three areas and figure out what the difference is.
BC
The only way that you can determine the health of a battery is to fully charge it and load test it. Shops worth going to will have the correct equipment to correctly test the battery correctly. They will also know how a C5 charging system works and will be able to correctly test the alternator output.
As for the car, the only way to figure out if theres a current draw problem is to do a current draw test. You can put brand new batteries in the car daily. If theres excessive current draw, there going to discharge the battery as it sits. My 02 ZO6 will sit for 2+ months and not have a starting issue. My 98 Coupe was the same. If you cant let the car sit for a short period of time without the battery discharging, you have some sort of problem.
On almost all C5's the actual battery voltage and or charging system voltage will be slightly lower on the interior dash gage and on the DIC than it is at the actual battery terminals. Make sure you compare the voltage in all three areas and figure out what the difference is.
BC
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Thread Starter
Racer
Joined: May 2006
Posts: 415
Likes: 0
From: Dallas TX
I am going to try a new battery since Ive had this optima red top for about 2 years. Its doing the same thing, had to jump the car twice today already. Im crossing my fingers thats its a battery problem and that theres not a current draw causing all this. I think Ill try a Duralast, Everstart, or Interstate this time, does it matter much?
Last edited by Tuk; Sep 12, 2007 at 06:11 PM.
Race Director
Joined: May 2005
Posts: 15,960
Likes: 21
From: West Norriton PA
St. Jude Donor '08
I am going to try a new battery since Ive had this optima red top for about 2 years. Its doing the same thing, had to jump the car twice today already. Im crossing my fingers thats its a battery problem and that theres not a current draw causing all this. I think Ill try a Duralast, Everstart or Interstate this time, does it matter much?
Race Director
Joined: May 2005
Posts: 15,960
Likes: 21
From: West Norriton PA
St. Jude Donor '08
Had the same crap happen last week on my brothers 99 FRC. Sent it over to the dealer by tow truck and latest tech bulletin repair done on it.
They now remove the lock plate and reflash PCM so fuel will not cut off.
You got till February 2008 for free fix.
Thread Starter
Racer
Joined: May 2006
Posts: 415
Likes: 0
From: Dallas TX
Don't ya just love it.
Had the same crap happen last week on my brothers 99 FRC. Sent it over to the dealer by tow truck and latest tech bulletin repair done on it.
They now remove the lock plate and reflash PCM so fuel will not cut off.
You got till February 2008 for free fix.
Had the same crap happen last week on my brothers 99 FRC. Sent it over to the dealer by tow truck and latest tech bulletin repair done on it.
They now remove the lock plate and reflash PCM so fuel will not cut off.
You got till February 2008 for free fix.
why would this happen immediately after putting in a new battery? Now I dont know if the original problem was fixed!! Do I have to tow it to the dealership or would a bypass module like this work? http://www.corvettesofhouston.com/pr...products_id=54I tried doing this from this walkthrough to no avail: http://www.ls1howto.com/index.php?article=24
"Now, put the key and and turn the car ignition to the ACC or ON position, but do not start the car. This should unlock the steering wheel. If it did, go on to PART 2, otherwise do the following: Turn the key off, remove the key, violently turn the wheel back and forth as much as you can, and try the key again. Repeat the process, and eventually the wheel will un-stick. Physical shock will nearly always unstick the motor temporarily."
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
First thing to do is make sure the NEW battery is fully charged. Make sure the batt terminals are correctly torqued to 11 ft/lbs.
Next read and post all your DTCs. Then clear them. Clean your key with an alcohol pad. Then reinsert ket and see if the column lock retract motor will unlock the steering wheel. If it doesnt while your turning the ignition key on and off,,,jerk the steering wheel side to side and see if you can get the lock bolt to release.
When the steering wheel unlocks, ORDER AND INSTALL a CLB!!!!!
Then your ALL SET!
BC
Next read and post all your DTCs. Then clear them. Clean your key with an alcohol pad. Then reinsert ket and see if the column lock retract motor will unlock the steering wheel. If it doesnt while your turning the ignition key on and off,,,jerk the steering wheel side to side and see if you can get the lock bolt to release.
When the steering wheel unlocks, ORDER AND INSTALL a CLB!!!!!
Then your ALL SET!
BC
Thread Starter
Racer
Joined: May 2006
Posts: 415
Likes: 0
From: Dallas TX
First thing to do is make sure the NEW battery is fully charged. Make sure the batt terminals are correctly torqued to 11 ft/lbs.
Next read and post all your DTCs. Then clear them. Clean your key with an alcohol pad. Then reinsert ket and see if the column lock retract motor will unlock the steering wheel. If it doesnt while your turning the ignition key on and off,,,jerk the steering wheel side to side and see if you can get the lock bolt to release.
When the steering wheel unlocks, ORDER AND INSTALL a CLB!!!!!
Then your ALL SET!
BC
Next read and post all your DTCs. Then clear them. Clean your key with an alcohol pad. Then reinsert ket and see if the column lock retract motor will unlock the steering wheel. If it doesnt while your turning the ignition key on and off,,,jerk the steering wheel side to side and see if you can get the lock bolt to release.
When the steering wheel unlocks, ORDER AND INSTALL a CLB!!!!!
Then your ALL SET!
BC
Race Director
Joined: May 2005
Posts: 15,960
Likes: 21
From: West Norriton PA
St. Jude Donor '08
Well I jerked the wheel side to side violently while switching the key from off to acc/on and the wheel unlocked...now, why would I have the need to have the column lock serviced if this has never been a problem in the past, and if I got it unlocked by myself? Is this problem going to persist now or am I okay to drive it?
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
GET A CLB!!!!!!!!!!!!!!! I have had on in my 98 and 02 ZO6 for YEARS! NO problems what so ever!
You can install it yourself. If you dont, some day, its going to lock again and NEXT TIME,,,,you might not be successful unlocking it.
BC
You can install it yourself. If you dont, some day, its going to lock again and NEXT TIME,,,,you might not be successful unlocking it.
BC
Intermediate
Joined: Apr 2007
Posts: 39
Likes: 0
From: Noblesville Indiana
Go out and buy a digital multi-meter... you can get a cheap one at walmart for like $20. Unless you buy one of the fancy ones with an inductive pick-up, you'll need to hook the meter up in series with the circuit.
This means that to do a current draw test, set the multi-meter to amps and disconnect the negative battery terminal. Place one lead of the multi-meter on the battery terminal and place the other lead on the end of the battery cable you disconnected.
I honestly don't know what the acceptable range for a C5 is... Bruceatlam said around 20 mA.
Also read through the instructions so you don't blow the fuse in the multi-meter (although this could be an inevitability if you have a serious current draw problem)