1996 blazer S-10
buddylee76
03-11-2005, 04:04 AM
Bought the truck 6 months ago. Previous owner replaced battery and alternator right before selling. a month ago battery completely dead after 1 week without running. Finally able to start after several attempts to jump it. No unusual electrical problems until earlier this week. Once again battery completely dead. Able to jump start on first attempt but only let the battery charge for 15 minutes. The next day battery completely dead again. Once again started after several attempts to jump it. Without a volt meter I successfully drove the vehicle with battery disconnected (I know this is not good troubleshooting method).
Battery tested good by oem, but was depleted.
Am wondering if alarm or other device is causing voltage drain ?
Battery tested good by oem, but was depleted.
Am wondering if alarm or other device is causing voltage drain ?
BlazerLT
03-11-2005, 04:28 AM
Learn how to properly charge a dead battery.
buddylee76
03-11-2005, 04:46 AM
[still doesnt explain why battery keeps dying
ricksza
03-11-2005, 05:57 AM
Just because they are new, doesn't mean that they're good. Have battery and charging system checked.
You could also have a draw in the system. Most common is the rear hatch is popped keeping the interior lights on especially if you have keyless entry. Need to test system with amp meter. Max draw with everything off should be under 35mA.
If you have a good charging system, and you disconnect the battery while running, the voltage will spike high (near 20 volts). Just enough to fry electronics such as ignition module, VCM, ABS module, etc. I've seen a tech (?) do this and cause $2000 worth of damage.
You could also have a draw in the system. Most common is the rear hatch is popped keeping the interior lights on especially if you have keyless entry. Need to test system with amp meter. Max draw with everything off should be under 35mA.
If you have a good charging system, and you disconnect the battery while running, the voltage will spike high (near 20 volts). Just enough to fry electronics such as ignition module, VCM, ABS module, etc. I've seen a tech (?) do this and cause $2000 worth of damage.
BlazerLT
03-11-2005, 02:38 PM
[still doesnt explain why battery keeps dying
Draining a battery completely dead and not completely chanrging it and allowing it to go dead again will sulfate the battery plates and ruin it.
I would check to see if you have a parasitic drain happening. With a multimeter hook up to the battery and see what the draw is from.
If there is a weird higher than usual draw happening (guys, help me out with the current value that is higher than normal), remove one fuse at a time from the fuse panel until the drain stops happening to isolate the circuit that is causing it.
Draining a battery completely dead and not completely chanrging it and allowing it to go dead again will sulfate the battery plates and ruin it.
I would check to see if you have a parasitic drain happening. With a multimeter hook up to the battery and see what the draw is from.
If there is a weird higher than usual draw happening (guys, help me out with the current value that is higher than normal), remove one fuse at a time from the fuse panel until the drain stops happening to isolate the circuit that is causing it.
ricksza
03-12-2005, 06:12 PM
Max draw should be 35mA with everything off. This will allow for the clock, radio memory and computer.
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