Battery cut off switch
kegeco
03-01-2009, 10:45 AM
I have a 2005 Grand Prix, but this issue could apply to any vehicle. I have a parasitic battery drain which I cannot find the source of. I figured the easiest way to deal with it is to install a battery cut off switch, but I would also like to be able to maintain current to the stereo so I don't lose the memory settings, etc.. Does such a switch exist.
Kegeco
Kegeco
BNaylor
03-01-2009, 12:35 PM
Welcome to AF.
That does not solve the problem and really not a good fix. You can check for parasitic drain with a mulitmeter (DMM) by checking for current draw at the battery negative cable. Then start pulling fuses, relays or wiring connectors to components using a systematic troubleshooting procedure.
Well discussed subject and I'll post more once you reply.
That does not solve the problem and really not a good fix. You can check for parasitic drain with a mulitmeter (DMM) by checking for current draw at the battery negative cable. Then start pulling fuses, relays or wiring connectors to components using a systematic troubleshooting procedure.
Well discussed subject and I'll post more once you reply.
brcidd
03-01-2009, 01:51 PM
You have just tdescribed the "Battery Buddy" the automatic battery disconnect when battery voltage drops below 12 volts, and auto reconnect when you try to start it-- I had one on my van for awhile- wife and daughter were always leaving lights on- worked good for about 3 yrs..I also bypassed the memory circuit to my radio.
But...I agree- why not just fix the original drain problem?....look at it as a challenge-- a game of sorts to track it down.. you just need some good wiring diagrams is all....
But...I agree- why not just fix the original drain problem?....look at it as a challenge-- a game of sorts to track it down.. you just need some good wiring diagrams is all....
BNaylor
03-01-2009, 02:09 PM
Actually the main brain behind it all is the body control module (BCM) so that is the automatic device that controls it all which also controls retained accessory power (RAP).
It depends on the battery reserve capacity rating so the first check is to make sure the battery is good and of the proper specs. The battery is supposed to hold its charge for approximately 30 days in normal situations.
Look at your battery's reserve capacity rating. Take that figure and divide by 4.
For example if the battery reserve capacity is 100. Divide by 4 = 25mA.
In this case cited if the draw exceeds 25 milliamps then you'll need to troubleshoot and find the source of the problem. A lot of the electrical has a constant battery 12 volts to include the starter and other electrical components even with the ignition switch to off including the PCM module.
It depends on the battery reserve capacity rating so the first check is to make sure the battery is good and of the proper specs. The battery is supposed to hold its charge for approximately 30 days in normal situations.
Look at your battery's reserve capacity rating. Take that figure and divide by 4.
For example if the battery reserve capacity is 100. Divide by 4 = 25mA.
In this case cited if the draw exceeds 25 milliamps then you'll need to troubleshoot and find the source of the problem. A lot of the electrical has a constant battery 12 volts to include the starter and other electrical components even with the ignition switch to off including the PCM module.
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