Archived alternator only showing 13 volts

[mfurrh55]

Hi everyone , got a problem, left friday in the jeep and came home sat. night, well sunday i went to start the Dodge truck and NOTHING, got to looking and i guess the grandkid turned on the pass. side seat heater, by the way is hooked into the battery and bypassing ignition system, well after couple days sitting it drained both batteries, which are pretty new, i charged the batts overnight and it starts but the voltage meter won't go up past 13 to 1350 volts, What should i check next?, Thanks for any advice, Monte

 

[AH64ID]

It is possible that the batteries are still low and the alternator can't get it above 13.5v with it's output.

I would drive it for 20-30 minutes and see where you are at.

 

[mfurrh55]

It is possible that the batteries are still low and the alternator can't get it above 13.5v with it's output.

I would drive it for 20-30 minutes and see where you are at.

I disconnected the cables and am trying to charge each battery separately and see if that works, when i put the charger on one batt, it showed that it wasn't completely charged, hopefully this will work and i can get the seat heaters hooked up to the ignition system, i just didn;t want to take the chance of burning out the tpm electrical, Thanks for your input, Monte

 

[B.G. Smith]

I doubt that the meter is very accurate? The regulated voltage should be in the 13.8-14.4 range, maybe even a little higher. If it still shows low, check voltage at the battery. With head lights on and heater fan on high it should maintain something above 13 volts. bg

 

[AH64ID]

Comparing my dash to voltage at the OBDII port and ECM it's pretty accurate.

 

[mfurrh55]

It has always shown to be over 14 volts, i did charge one battery up more and it is showing right at 14 volts, i am charging the other now to see if it will bring it back up to where it usually is, Thanks for info, Monte

 

[mfurrh55]

Thanks AH64ID, I'm now showing around 15 volts, after charging up the other battery separately,needle is back up to where it usually resides, Thanks for all the input, with this website a person always knows where to turn to for advice, Monte

 

[MMeier]

For my fleet I bought a 1.25 amp trickle charger/ maintainer and try to get everything on at every other month . Both Dodges the race car, chevelle and the battery in the race car trailer sometimes sit way longer then I want them too !

 

[Tuesdak]

I disconnected the cables and am trying to charge each battery separately and see if that works, when i put the charger on one batt, it showed that it wasn't completely charged, hopefully this will work and i can get the seat heaters hooked up to the ignition system, i just didn;t want to take the chance of burning out the tpm electrical, Thanks for your input, Monte

Use a relay that turns on with the ignition to "enable" the seat heaters. The relay contacts connect to the battery and then to the seat heater switches. Coil of course to hot ignition and ground with a surge suppression diode across it. In other words cut the seat heater wire, put relay in and wire relay with diode to hot ignition source. this will keep the seat heater current out of the TPM.

 

[mfurrh55]

Use a relay that turns on with the ignition to "enable" the seat heaters. The relay contacts connect to the battery and then to the seat heater switches. Coil of course to hot ignition and ground with a surge suppression diode across it. In other words cut the seat heater wire, put relay in and wire relay with diode to hot ignition source. this will keep the seat heater current out of the TPM.

Ok, Thanks for the info, Need to get it done before this happens again, Monte