I have a 2016 Dodge charger scat pack 6.4 l engine and my ECM voltage regulator stopped functioning so I replaced it with an external voltage regulator and now I'm having issues with low voltage it's stuck at 11.7 volts and if I turn on headlights radio it goes down below 10 volts and it needs to be between 13 and 15 volts I feel like it might be a ground issue but I believe I have rectified the ground issue unless there is someone out there that can relate with what I'm going through... I had the alternator rebuilt I installed a brand new modified driver in the alternator I got a brand new AGM battery with 850 CCA
If there is anyone out there that can help me out with this I will be greatly appreciated in the Lord will bless you and abundance a hundredfold thank you in advance

 

I have a 2016 Dodge charger scat pack 6.4 l engine and my ECM voltage regulator stopped functioning so I replaced it with an external voltage regulator and now I'm having issues with low voltage it's stuck at 11.7 volts and if I turn on headlights radio it goes down below 10 volts and it needs to be between 13 and 15 volts I feel like it might be a ground issue but I believe I have rectified the ground issue unless there is someone out there that can relate with what I'm going through... I had the alternator rebuilt I installed a brand new modified driver in the alternator I got a brand new AGM battery with 850 CCA
If there is anyone out there that can help me out with this I will be greatly appreciated in the Lord will bless you in abundance a 💯 fold thank you in advance

 

Are you saying the voltage regulator the provides a regulated 5V to the Engine Control Module (ECM) failed and you replaced with an external regulator, or are you referring to the voltage regulator for the alternator/charging system? Did you replace with an LM7805 linear regulator or a switching regulator, or some other regulator.

-Rod

 

[QUOTE=SHO Rod;3595279]Are you saying the voltage regulator the provides a regulated 5V to the Engine Control Module (ECM) failed and you replaced with an external regulator, or are you referring to the voltage regulator for the alternator/charging system? Did you replace with an LM7805 linear regulator or a switching regulator, or some other regulator



I used a VR125

 

I'm pretty sure that your 2016 has an intelligent charging system that controls the output of your alternator rather than just relying on an old-school external regulator. I'm not sure how you connected the VR125 to your existing system, but if you only used the existing wires the ECM is probably really confused and hence why your alternator is not putting out the correct voltage.

What was the "modified driver" that you had installed in the alternator when you had it rebuilt? What was the issue before you had the alternator rebuilt that caused you to have it rebuilt?

-Rod

 

Rebuilding the alternator and installing a new AGM battery and replacing the battery current sensor on the negative side of the battery... it was pretty much a process of elimination that I put the car through the only thing left after my research because it was still doing the same thing with the low voltage I installed the modified driver believing that that would help but it did not still at 11.7 volts

 

Do you have access to a professional-grade scan tool to monitor the charging system and see if the charging system is requesting the alternator to provide output? Have you confirmed the system voltage with a multimeter at the battery?

-Rod

 

[QUOTE=SHO Rod;3595365]Do you have access to a professional-grade scan tool to monitor the charging system and see if the charging system is requesting the alternator to provide output? Have you confirmed the system voltage with a multimeter at the battery?

Yes I did use a multimeter and confirmed that it's only putting out 11.3 to 11.7 volts front and back and behind the alternator and I also did confirm with the multimeter and that the voltage regulator is putting out the same input an output

 

If that voltage regulator is a zener diode based transistorized regulator, it will not begin to regulate until the output voltage is at least several tenth's of a volt above the set regulation point, so it would make sense that the output is tracking with the input at less than 12 volts. I would expect some amount of voltage drop across the regulator though if it's connected properly.

If you have access to a professional grade scan tool or an oscilloscope you could check to see if the ECM is requesting the alternator to provide higher output. The scan tool would be the preferred, easier method to help troubleshoot the alternator output.

-Rod