If I had to guess, I'd say what you are hearing is the AIR pump.
Bad Battery..
Thread Starter
Drifting
Joined: Jan 2008
Posts: 1,752
Likes: 62
From: New Madison Ohio
Bad Battery..
While cruising my volts are only showing anywhere from 13-13.5 volts. Yesterday was sitting at the drive-thru at Sonic and car almost quit and battery volts was 12.5. I drove to my dad's house and discussed the situation with him (retired gm mechanic 38 years). I told him my alternator whines in the morning at first start up. He advised either the battery was bad or the alternator was going. I stopped by Autozone on the way home and had both tested. The alternator tested good and the battery was at 12.5 volts and the display even said "bad battery". So checked on a couple of prices and will probably try and get by with the current one (red top optima) and maybe get new one in the spring. What you guys think?
Thread Starter
Drifting
Joined: Jan 2008
Posts: 1,752
Likes: 62
From: New Madison Ohio
Well lets see, what things would be impacted by a battery that is going low. Hmmmmmm. Ohhh Ya. Relays. Where are there relays in the C5???
Well theres one in the GM K Harness if you have an automatic that has the Column Lock service from GM done. And there's another in the EBCM for the anti lock brakes but who needs anti lock brakes. There is another for headlights and come to think of it for most other high draw electrical devices. And there are a bunch in the BCM.
Naaaaaa, go ahead and drive it till it stops when the red top craps the bed completely. Then just get it towed home and put it into storage until the spring. Once you have the new battery next spring, you can see what fell out of your decision. Post back in the spring so we can all learn.....
Well theres one in the GM K Harness if you have an automatic that has the Column Lock service from GM done. And there's another in the EBCM for the anti lock brakes but who needs anti lock brakes. There is another for headlights and come to think of it for most other high draw electrical devices. And there are a bunch in the BCM.
Naaaaaa, go ahead and drive it till it stops when the red top craps the bed completely. Then just get it towed home and put it into storage until the spring. Once you have the new battery next spring, you can see what fell out of your decision. Post back in the spring so we can all learn.....
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
Something is not right here...... If it were me, I would properly charge the redtop and then have it fully tested.
Remove the battery from the car. Use a set of jumper cables and parallel in a standard lead acid battery. Put the battery charger on the standard Lead Acid battery on a high current 10-12 amp charge. If your RED TOP has ever been drained to where it was almost dead, this procedure is suppose to allow it to fully charge properly. It fixed mine.
After you get the battery issues sorted out, install the battery and start the engine. Use a VOLT METER and measure the voltage at the battery terminals and see what actual battery voltage is. Should be right around 14 VDC.
IF,,,,,, its lower than expected,,,, go get those battery jumper cables.
Attach one of the cables (pick the RED or BLACK cable, it doesn’t matter which one you use) to the BATTERY POSITIVE terminal and the other end of that cable to the BATT terminal on the back of the alternator. (The terminal under the black boot)
Remeasure the battery voltage on the battery terminals with a volt meter. IF,,,,,,,, the voltage increases, you have a bad connection between the battery and the alternator.
99% of the time, the problem is the connection on the starter solenoid. The connection gets dirty, corroded, loose, damaged etc... and the alternator cant charge the battery.
Give that a look see!!
Bill
Remove the battery from the car. Use a set of jumper cables and parallel in a standard lead acid battery. Put the battery charger on the standard Lead Acid battery on a high current 10-12 amp charge. If your RED TOP has ever been drained to where it was almost dead, this procedure is suppose to allow it to fully charge properly. It fixed mine.
After you get the battery issues sorted out, install the battery and start the engine. Use a VOLT METER and measure the voltage at the battery terminals and see what actual battery voltage is. Should be right around 14 VDC.
IF,,,,,, its lower than expected,,,, go get those battery jumper cables.
Attach one of the cables (pick the RED or BLACK cable, it doesn’t matter which one you use) to the BATTERY POSITIVE terminal and the other end of that cable to the BATT terminal on the back of the alternator. (The terminal under the black boot)
Remeasure the battery voltage on the battery terminals with a volt meter. IF,,,,,,,, the voltage increases, you have a bad connection between the battery and the alternator.
99% of the time, the problem is the connection on the starter solenoid. The connection gets dirty, corroded, loose, damaged etc... and the alternator cant charge the battery.
Give that a look see!!
Bill
Melting Slicks
Joined: Jul 2006
Posts: 2,332
Likes: 31
From: Silver Spring MD
Mine failed to crank when I turned the key but radio, lights, accessories worked
Was weak cells on a 6 year old battery.
Got a new one at Sams with over 1000 cranking amps
Don't need to spend a fortune on the Optima batteries.
Was surprised that it wouldn't crank but everything else worked.
Thought I might have a bad ignition switch. Charged it and it started.
Check for voltage drop like at the starter terminal and clean the battery posts and connectors before replacing but if it is bad get a new one NOW if you plan to use it during the winter. Heat and Cold are the 2 hardest things on a battery.
Got a new one at Sams with over 1000 cranking amps
Don't need to spend a fortune on the Optima batteries.
Was surprised that it wouldn't crank but everything else worked.
Thought I might have a bad ignition switch. Charged it and it started.
Check for voltage drop like at the starter terminal and clean the battery posts and connectors before replacing but if it is bad get a new one NOW if you plan to use it during the winter. Heat and Cold are the 2 hardest things on a battery.
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