2000 Dodge Stratus Battery Light Lit On Dashboard Month Ago Determined Wasn T

2000 DODGE STRATUS
20,400 MILES
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I have a 2000 Dodge Stratus and the battery light is lit up on the dashboard. A month ago I determined the battery wasn't being charged sufficiently, so I replaced the alternator. That didn't help, so I replaced the ECM since that's where the voltage regulator is. Yesterday we replaced the battery and the light still stays on. I am reading 13,25 volts at the battery when idling. With the headlights and fan motor on high it drops to about 12.7v. Any suggestions?
Feb 10, 2013 at 2:57 AM
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CARADIODOC
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Have the new alternator load-tested on the car. Don't take it off and haul it to a store. I suspect you're going to find it only produces around 30 - 35 amps which will be exactly one third of what it should be capable of, and "Ripple" will be very high. Those are the signs that one of the six diodes has failed. 35 amps is not enough to handle the entire demand of the electrical system so as you turn on more stuff, the battery makes up the difference and starts to discharge.
Feb 10, 2013 at 3:39 AM
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CARADIODOC
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I forgot to mention too that to be accurate, you have to raise engine speed a little when checking alternator output. AC generators, (alternators), are not very efficient at low speeds.
Feb 10, 2013 at 3:41 AM
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