Dead battery?

[ecom]

I haven't taken the battery to get it tested yet. Using a DMM, the car battery open voltage is 12.0V.

After jump starting the car, voltage at battery terminals is 13.6V. Pull the throttle cable and voltage goes as high as 14V. Drove around for about 20 minutes and then let the car idle for 20 minutes. Shut off the car and the open voltage on the battery is still 12.0V and will not start on it's own.

Attempting to start results in rapid clicking noise and all the radio turning off.

 

[JMWarren]

Sounds like the voltage is dropping under the starter load. I bet it'll fail a load test. How old is the battery?

 

[XZeroII]

take the battery to batteries plus. They will test it for free.

 

[StageLeft]

Clicking is classic sign of bad bat and if after 40 min it's still no good I say landfill that bizatch. Or recycle or whatever with it

 

[Ronstang]

Take the battery to the auto parts store to check if it is good. If bad replace, if good then go home and put it back in an if the problem persists you have a bad connection/cable...which would also keep it from charging properly.

 

[brblx]

Clicking is classic sign of bad bat

no, it is a sign of a discharged battery, not a bad one. a battery that is bad (dead cell or other major internal problem) generally will not even have enough voltage to click the solenoid.

12.0v indicates a fairly discharged battery, but that may not be the root of the OP's problem. if it's charging 13.6v at the battery, it is unlikely that the charging system is at fault- although it is possible to have normal voltage output but not enough amperage. you need an inductive clamp for your DMM to measure that.

i would go ahead and have the battery fully charged and tested, which parts stores will do for free, as mentioned above. they should be able to tell you if the charging capacity is severely reduced, which can happen as batteries age and may be your problem.

if the batt checks out okay, check your cables. look for voltage drop across your ground (batt to engine) and power (batt to big starter terminal). you need to check them while cranking.

 

[StageLeft]

It might not be the battery but I would bet good money that it is. The battery is far more likely to be at fault here than anything else in the system.

A truly dead battery won't click the solenoid but a mostly dead one (from age and lack of ability to feed amps) will. That's what happened with me last year and a highly discharged battery does create the machine-gun clicking.

Even an effectively dead battery can show desired volts at rest but as soon as you try to demand any watts out of it the volts go through the floor.

 

[BUTCH1]

It's dead Jim!!!!

 

[ecom]

Battery is bad and replaced with one from Costco. For $60 + $9 core, I think it's the best deal around.