I see often, on auto based websites, where some poster decides to grant the voltage regulator with powers and abilities and logic, it simply does not have. 2 months later the same topic comes up and somebody in that former thread, repeats the assigned wizadry to this mystical device, along with a whole bunch of other incorrect information, whether it is located in a computer or inside the alternator or located on the firewall. Soon the minstrels in the hills are touting the incredible IQ of a voltage regulator, imbuing it with powers it does not have, as it is a brain damaged hamster god in the corner awaiting the whip to get back on its wheel.
I had to stop participating on such forums as no matter what, the same incorrect battery and voltage regulator myths keep being repeated.
The VR as an all knowing high IQ god, comes up every so often, and today Popeye was one of its worshippers.
Keep in mind there is only one model year difference between Heron's Dodge and my own.
The engine computers are interchangeable with only slight differences. The voltage regulator is located within it.
When i put a permanent digital voltmeter on my dashboard wired to the battery terminals, not tapping into some easier to reach circuit, 14.9 or 14.7v was always the voltage right after starting, except in cases with a super depleted battery where 50 to 60 amps at idle, is not enough to bring it instantly to 14.7 or 14.9, then the voltage was climbing towards that level, and would climb faster with more rpm and then drop at idle.
A few minutes later, 13.7v, no matter what. rpm had no further effect, unless the battery was so depleted and engine rpm so low that its amperage output could not maintain 13.7v, but this was pretty rare.
Occasionally, when driving after a frustrating 13.7v was all that was allowed, it would spike to 14.9 or 14.7v, for NO reason I could ever determine. It would usually only last for a short while before dropping back to 13.6v or 13.7v. Very seldomly, 14.1v would occur, again there was never any factor that i could determine as to what could be effecting the voltage change, other than bipolar bat crap crazy factor.
One time I was driving around town with my engine cover off. I noticed that sometimes cool air was entering the passenger compartment, but then the thermostat would open and instantly there would be huge amounts of radiator heat gushing across engine into engine compartment.
The engine computer has an air tube which splits off from the engine's cold air intake, so some portion of the air entering the engine is actually sucked through the engine computer, where the voltage regulator is located. I thought this could be a contributing factor to why the insane voltage regulator was behaving as it did. When the thermostat opened and flooded the engine compartment with radiator heat, the hotter air flowing through engine computer would trigger a lower voltage. Eureka I thought. I found a way to influence the voltage regulator, I could perhaps have it suck heat from a cooler location and allow it to hold 14.7v for longer.
But when testing again driving with engine cover off, the 13.7 vs 14.7v rarely had any correllation to when I felt a blast of radiator heat from the t stat opening. I went further and made a temporary carboard tube to suck nothng but cold air from in front of engine through the engine computer. No effect on voltage. Balls.
Back to the bat crap crazy theory and being pissed off the battery was being charged at 1/3 the potential rate, as 1/3 the amps flow at 13.7 vs 14.7 reaching battery terminals.
Chryslers whose internal engine computer voltage regulators fail, the only traditional fix was a new 250$ + remanufactured engine computer, as using an external regulator would illuminate teh check engine light and the engine computer would no longer take readings from 02 sensor or TPS or CTS to influence spark timing. The CEL comes on and the engine runs crustier with less power and efficiency, AND will not pass any emissions test.
One outfit came up with a way to trick the engine computer into thinking it was still attached to the alternator, and allow the use of an external voltage regulator.
They use a 50 watt 10 Ohm resistor in between the original two 'field wires' that attach to the back of the alternator. Easy Peazy, the engine computer does not know it is bypassed, the CEL stays off, the engine sensors still read and influence timing and fuel flow for power and mpg.
Then one uses an external regulator instead and the field wire from it goes to one of these now empty field terminals. The other field terminal gets grounded.
I use a Transpo540HD, which has an adjustable voltage potentiometer inside of it. There are MOPAR voltaeg regulators that also have such a potentiometer, the 540HD is for a Ford, but knows not what type of vehicle it is in, as it is not a fucking omniscient omnipotent god.
The 540 HD has 4 terminals. The body of the VR must be well grounded
A terminal is for Always on.
I hook to the positive output terminal of alternator, but ideally this would go right to battery + instead, as it is the voltage sense line, as well as providing the field current sent to the rotor.
S terminal is a switched ignition source. Very little power flows through this wire, it merely turns the VR on or off. I found an unused badly oxidized hooded male quick connector dangling under my dash, and found it only became live after the engine started. Perfect for turning on the VR.
F terminal is the field wire, which goes right to one of the terminals on the back of the alternator, the other field terminal is grounded to the alternator body.
I terminal is for the Idiot light, if i VR fails it will illuminate a light. I ignore this terminal as my voltmeters will tell me if it or the alternator has failed. No steenking light needed.
I removed the tiny 2k ohm voltage trimpot inside the transpo, and soldered wires to the legs of where it resided, and ran them to a 10 turn 2 k ohm potentiometer located next to my voltmeters and ammeter on dashboard.
Spin a dial to change the voltage, watch the amperage into the battery rise or fall in response. Enlightening, empowering, ultimately satisfying. I can almost always charge my battery as fast as safely possible, the limiting factor is its rpm and ability at lower rpms to make enough amperage to bring the battery to or hold the battery at 14.7v.
14.7v is the limit however. if the engine computer sees 14.8v for 30 seconds when it is expecting the 13.7v it wouls have chosen if it were still in control, the check engine light comes on and it defaults to running crustier with worse MPG. note that the CEL will go out the next engine start, but the engine still does not respond to sensor inputs. Need to reset engine computer if the CEL light comes on. I just turn a switch to remove the battery from it, but others might have to remove the battery cable from battery to accomplish this. The engine will run crusty the next cold start while it learns the sensors and readjusts to the engine and operating conditions.
https://www.ebay.com/itm/FORD-External-V...XQHxVRgOiz
https://www.ebay.com/itm/Adjustable-Exte...100623.m-1
https://www.ebay.com/itm/Dale-RH-series-...SwAghatYF7
The 50 watt resistor gets quite hot. I attached it to a larger heatsink and wired it securely it to the nearby trransmission dipstick. if I had to do it again I'd buy the 100 watt 10 ohm resistor instead, but likely still thermal epoxy it to a larger finned heatsink even though it likely does not care. They are designed to resist heat.
https://www.ebay.com/itm/1-2-4-6-8-10R-O...Sw-5pey3J3
I did not know the value of this resistor, the outfit which figured out the right value, charged me 23$ plus exorbitant shipping for this ~3$ part. they ground off the value printed on the resistor.
The call it a 'field replacement module"
https://store.alternatorparts.com/hd-ext...t-kit.aspx
What is good, is that Dodges do have an externally regulated alternator rather than internal. External is 1000 times more desirable when battery charging time/efficacy is a factor, and boaters will go to great lengths to modify their internally regulated alternators in order to allow for external regulation.
My engine computer can be hooked easily back up to the Alternator, but I have bought a second transpo540HD, to have as a backup, and or to use on a second alternator, so that is extremely unlikely to ever occur.
I also added finned heatsinks to the underside of the voltage regulator, and being the ventilation lunatic I am, a 60Mm fan too. If My external VR fails it will unlikely be due to excessive heat, which is the root cause of most electronics failures.
Lots of newer GM vehicles and some other brands will have a hall effect sensor ring over a battery terminal. They will know how much current is flowing into and out of the battery. They intentionally keep the battery about 80% charged. They turn off field current during accelleration to removeall alternator load from the engine, and thus squeeze out tiny improvements in MPG. Tiny improvements in their fleet average MPG means many millions in executive bonuses for meeting CAFE( corporate average fuel economy) standards, which is also a major reason that motor oils are also getting thinner and thinner, for tiny reductions in drag and higher mpg. The same engines in other countries without CAFE, spec thicker oils. Thicker oil can protect the engine better with higher oil film strength.
Most high mileage vehicles the engine is still Ok even with 0w-20 its whole life when it goes to the junkyard.
This alternator manipulation kills batteries prematurely as they are always undercharged, intentionally. The computers will only spike voltage higher when letting off the gas and coasting or when braking, and perhaps some other times when it will be least detrimental to fuel economy, and if the battery were fully charged then the alternator would not have to make much amperage at all when the regulator spikes the voltage, so they keep it in the 80% range, so it can.
So even the newest and smartest of voltage regulators that come stock in modern vehicles, cant and wont change voltage in order to quickly recharge the battery, they change voltage ONLY to squeeze out tiny improvements in fuel efficiency, and sacrifice the battery life in order to do so.
Dishonest,, repugnant, and self defeating, as more energy is wasted in transporting and recycling prematurely failing batteries than is saved by the tiny gains in mpg achieved by mpg friendly voltage regulation.
But it looks good on paper and maximum executive bonus is always a top consideration.
So the 'smartest' of newer stock vehicle voltage regulators, which could infer battery state of charge, do so not to quickly and fully recharge the battery, they do it for CAFE, and sacrifice the battery in order to do so.
My voltage regulation is completely manual. if the battery is accepting more than 0.5 amps, I keep it at 14.7v, if it is accepting 0.5 amps or less I choose 13.6v. I do have a battery temp sensor, i will adjust up or down slightly according to what it reads but never higher than 14.7v.
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