Has anyone ever done a external voltage regulator on a 4th gen? Is it possible? I’m currently trying to run an external voltage regulator, I have it set up the way it should be, but when I test the voltage on my battery it doesn’t show it to be working/ kicking the alternator on to charge. If it is possible, am I doing something wrong?

 

seen this in the 1st gen section
https://dodgeforum.com/forum/1st-gen...onversion.html

 

I was reading up on that, would it be the same concept on a 4th gen as well? For some reason the external voltage regulator that I have installed on the truck, isn’t working

 

If I'm not mistaken, the newer 4th gen Rams have a "smart" charging system which controls the alternator output by the PCM based on the battery state of charge (SoC), demand on charging system, battery age, and probably a few other parameters. If that's correct, your external voltage regulator is probably interfering with the PCM's control of the charging system. You don't mention what year yours is, but you may want to see if yours has a smart charging system and if so, contact the voltage regulator manufacturer to see if see if they have a system that will work for you.

Edit: I found this in the service manual information for my 2014 Ram:
"The charging system is turned on and off with the Powertrain Control Module (PCM) and ignition switch with engine running. The field circuit will not be energized until engine is running and ignition switch on. This voltage is connected through the PCM and supplied to one of the generator field terminals (Gen. Source B+) at the back of the generator. The generator is internally grounded. The generator regulates the field using pin-1 of the field connector (high side driver).

"The generator is driven by the engine through a serpentine belt and pulley, or a decoupler pulley arrangement.

"The PCM receives a voltage input from the generator (5) and also a battery voltage input (7) from the Power Distribution Center (PDC), it then compares the voltages to the desired voltage programed in the Electronic Voltage Regulator (EVR) software, and, if there is a difference it sends a signal to the generator EVR circuit to increase or decrease output. It uses a Pulse Width Modulation (PWM) to send signals to the generator circuitry to control the amount of output from the generator. The amount of DC current produced by the generator is controlled by the EVR circuitry contained within the PCM (1).

"All vehicles are equipped with On-Board Diagnostics (OBD). All OBD-sensed systems, including EVR circuitry, are monitored by the PCM. Each monitored circuit is assigned a Diagnostic Trouble Code (DTC). The PCM will store a DTC in electronic memory for certain failures it detects.

"The Check Gauges Lamp (if equipped) monitors: charging system voltage, engine coolant temperature and engine oil pressure. If an extreme condition is indicated, the lamp will be illuminated. This is done as reminder to check the three gauges. The lamp is located on the instrument panel.

"Voltage is monitored at the B+ terminal stud to insure it is connected. If the B+ cable is loose, the PCM will shut down generator field. Because of this new feature, pin-2 of the field connector is internally connected to the B+ terminal."

-Rod

 

Think my question would be, why are you installing an external regulator in the first place?

 

mine is a 2012

 

i had some issues about a few weeks ago with my truck during the rain, it’s working fine now, but my voltage is reading around 15 volts from battery to alternator, but now currently my map lights will dim and then brighten, my sub would cut off and on due to the voltage not being consistent. I had it tested and it came to be the voltage regulator

 

so you have an aftermarket stereo system...how many watts and are you using capacitors?

 

it’s a 250 watt sub and just a fuse that is hooked up to the battery. No capacitor

 

is the system is normal when the sub is not in use?