2005 dodge Durango battery light

[Robert Leon]

So I know it's not a ram but my wife's battery light came on today. I just bought the battery 2 months ago from AAA. Why is this light coming on?

 

[jwheeler]

Light will come on when battery charging voltage is low. Can happen with a bad battery or failed alternator. Inspect the battery cables. Make sure they are clean and tight. Check the battery voltage with the car running and report back.

 

[JPT]

I think it could come on if the battery is getting too hot from charging too, since there is that sensor under the battery.

 

[jwheeler]

I think it could come on if the battery is getting too hot from charging too, since there is that sensor under the battery.

That sensor under the battery is not to monitor battery temp for regulation purposes. It is just another reference for ambient temp. Has nothing to do with the battery light.

 

[Robert Leon]

Thanks guys! I will check tonight after wrk and let you know.

 

[JPT]

That sensor under the battery is not to monitor battery temp for regulation purposes. It is just another reference for ambient temp. Has nothing to do with the battery light.

Are you sure. It usually is used to prevent overcharging of batteries. It usually is the battery temperature sensor...

http://www.justanswer.com/dodge/110cx-test-battery-temperature-sensor.html

The BTS is used to determine the battery temperature and control battery charging rate. This temperature data, along with data from monitored line voltage, is used by the PCM (ECM Diesel) to vary the battery charging rate. System voltage will be higher at colder temperatures and is gradually reduced at warmer temperatures.

The PCM sends 5 volts to the sensor and is grounded through the sensor return line. As temperature increases, resistance in the sensor decreases and the detection voltage at the PCM increases.

The BTS is also used for OBD II diagnostics. Certain faults and OBD II monitors are either enabled or disabled, depending upon BTS input (for example, disable purge and enable Leak Detection Pump (LDP) and O2 sensor heater tests). Most OBD II monitors are disabled below 20°F.

Read more: http://www.justanswer.com/dodge/110cx-test-battery-temperature-sensor.html#ixzz3KCCDhX00

 

[jwheeler]

Hmmm. You could be right. I believe low voltage is a more likely cause for that light than the sensor. I would check that first.

 

[JPT]

Hmmm. You could be right. I believe low voltage is a more likely cause for that light than the sensor. I would check that first.

I agree. It is just another possibility.

 

[Robert Leon]

Well I check the battery and I'm getting about 12.55 volts. The alternator is getting very very hot when I start it. I'm getting over 15 volts when I start it.

 

[Robert Leon]

Solved the problem. Bad alternator. Everything is back to normal.

 

[jwheeler]

Good to hear. 15v is too high.

 

[Robert Leon]

Thanks guys!