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WTF indeed. Makes me wonder if the voltmeter is as fake as the oil pressure gauge.

Now I gotta try using a real voltmeter and see what it says. Or better yet, you do it Don. I probably won't be starting mine for a while.
 
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WTF indeed. Makes me wonder if the voltmeter is as fake as the oil pressure gauge.

Now I gotta try using a real voltmeter and see what it says. Or better yet, you do it Don. I probably won't be starting mine for a while.
Maybe I will just continue to do the double push thing and not worry about it! Just as well drive a Ford and worry about the freaking CP4 coming apart! LOL
 
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Maybe I will just continue to do the double push thing and not worry about it!
^^^ 100% Agreed! The less you know about what makes you Gen-4 Ram tic the nicer your life will be.🥰
But if you're curious, here's some Gen-4 fun facts. . .

1.) Your gauges and readings on your dashboard are a fantasy. They have little reference to what is actually going on in your truck. The FCA service manual even explains that this is done to reduce the number of customers bringing their vehicles in for warranty repairs because of gauge readings that they "think" are out of range. Thus FCA displays what they feel customers expect to see on their gauges, NOT what is really going on with the engine.

2.) Like just about everything else on your dash the voltmeter readings on your dash are synthetic.
Additionally the grid heater 'on' indication is a fake too. . .

(I could explain how its fake but I'm already too long here) 😐

What you need to know is that your grid heater can be on for extended periods of time, burning away while you drive without you knowing it.
This is one of the ways people burn grid heater bolts and never know it until knock, knock, knock, BOOM!

However...
If you were one of those types to "worry" about such things you could always install a voltmeter that directly reads 'real' battery voltage, and an indicator lamp that only illuminates when the grid heater is actually getting power.
Shown below on my 2016 Longhorn's console side panel...

IMHO that little red indicator lamp is more critical than the 'true' reading voltmeter since you need to know that the grid heater is truly NOT getting power regardless of what the indication the ECU is sending you or what the battery voltage might be.(y)

But then again I wouldn't worry too much about it.
Honestly... What could possibly go wrong?

Regards,
-Ej- 🍺
 

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Thanks Jake!
Just seeing this, appreciate it.
The dumpster behind any large FCA dealership is a prime source for obtaining slightly used grid heater plates to harvest resisters (coils) from to build the project. ;)

-Ej- 🍺
 

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Since when is the voltmeter synthetic? Mine has always been within .1 volts of my handheld whenever I’ve been curious about charging issues as draw with my snowplow.
 

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Since when is the voltmeter synthetic? Mine has always been within .1 volts of my handheld whenever I’ve been curious about charging issues as draw with my snowplow.
It would be interesting to get a calibrated variable DC power supply and run it from 7 to 17 volts on the DC bus and see how well you dashboard readout would fair.

And you say you get readings to within a "tenth" of a volt on your dash readout??? Really?
Show me. 😐
 

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Your display is for your fancy, gentleman's cruiser, not my work truck. My truck shows whole numbers only, and only when I select that function, but the idea is the same. If it reads 14 and I get 14.1 on my DVM, that’s a tenth , correct? It mostly charges around 13.5-8 in warm weather, 14.1-4 in colder times with an average load. I’ve never seen less or more than that spread no matter the temps. Even with repeated cycles of the plow angle or lift. The only time it’s dropped below that is with the grid heater or holding the plow motor engaged against a stop. The plow motor is good for over 100 amps but the weak link in the trucks charging system is the wire from the alternator to the battery. It’s too light to pass the full output of the alternator. Now, please tell me when the voltmeter became an algorithmic display.
Ps. You can save the “ show me” crap for someone you think will be effected by it.
 

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Good reply.
I‘d expect nothing less.👍
 

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Question for you guys. I unhooked my grid heater from the battery itself about 2 years or so ago. Over that time I noticed that during the warmer months the voltage displayed on my CTS2 is 13.2-13.6 (ish) range. In the colder months it hangs around >14 volts. Is this a sign that the PCM is deciding that it is cold out and should be supplying enough power to heat the grid heater even though it's unhooked? Even after completing a multi hour road trip it's charging at or above 14 volts. Just a curious observation and interested in ya'lls thoughts.


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Please understand that my intent is NOT to argue or say you are wrong. On the contrary, I am very interested in how your simple & effective 'fix' functions.

I went thru a lot of aggravation and expense to load the IBS with 200 amps via a dummy load mounted behind my engine fan so the BCM 'sees' a healthy grid heater load when the grid heater is in reality disconnected.

Normally, without simulating a 200 amp grid heater load at the Intelligent Battery Sensor every time the Intake Air Heater Relay cycles, the PCM will throw a P2609, light the MIL, and block the remote start feature.

What you did sounds exactly like the @Jimmy N. method but in your case you still have a fully functioning remote start feature.
Nice! (y)
hi. i hope you got your remote start to work. so far mine is working fine. also if I didn't tell it right. my grid heater relay is still hooked up, so the pcm can still control it. I just hooked the big wire from the relay to the grid heater. so when its cold enough the relay will still come on but no power is going to the grid heater. i could be wrong but i think the pcm is just looking for a current drop on the relay coil when it is commanded on. my old 2010 was also grid heater deleted and everything was working fine and one morning I started the truck and a few seconded latter the engine light came on. I also noticed i didn't hear the grid heater come on. I looked it over and found one of the relay coil wires came lose. tightened the wire then cleared the code. the truck was back to running like it should.
 
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That’s part of what I referred to in my previous post. Your charging rate is based at least partly on battery temp. That’s the sensor under your drivers side battery. Warm batteries require less charge.
 

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Question for you guys. I unhooked my grid heater from the battery itself about 2 years or so ago. Over that time I noticed that during the warmer months the voltage displayed on my CTS2 is 13.2-13.6 (ish) range. In the colder months it hangs around >14 volts. Is this a sign that the PCM is deciding that it is cold out and should be supplying enough power to heat the grid heater even though it's unhooked? Even after completing a multi hour road trip it's charging at or above 14 volts. Just a curious observation and interested in ya'lls thoughts.


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These trucks do temperature compensated charging. As temperatures get cooler the voltage required to fully charge increases. At 0f the voltage is close to 15v.

Sent from my SM-T500 using Tapatalk
 

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These trucks do temperature compensated charging. As temperatures get cooler the voltage required to fully charge increases. At 0f the voltage is close to 15v.

Sent from my SM-T500 using Tapatalk
I don't know if it is by design. Decades ago Delco alternators, 10SI, 12SI, 27SI's, did the same naturally, no ECM's controlling them.
 

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I don't know if it is by design. Decades ago Delco alternators, 10SI, 12SI, 27SI's, did the same naturally, no ECM's controlling them.
Everything that is old is new again at some point...lol. To your point, I'm not certain that continuing to make vehicles even more hopelessly complicated is the right answer, for anyone but the service departments. Sometimes simpler is better.
 

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I have a 15 6.7 ram. It started randomly loosing boost, then randomly coming back. I replaced the map sensor, #2 nox sensor cause it threw a code, and now I have the grid heater voltage to high code. I'm not a master mechanic, but doesn't seem that would effect my boost, or am I wrong? At first start up in the morning, letting the heater cycle or not, the voltage fluctuates from 13-14, give or take, reading the factory voltage gauge. And obviously the lights dim, then bright as the fluctuation happens. Is that normal? Or bad solenoid? My boost loss has dramatically improved, but still a short-term loss here and there. Noteworthy maybe, once it's at full operation temp, as on 15-20 mile drive, I have no boost issues
 
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