Time for a new Alternator

[dave110]

IAT, ECT, and the battery temp sensor all work together to control when they come on and off. Speed sensor plays a part too turning them off at 18mph I think. Mike taught me that it's possible to have 100+ IAT and 190 ECT and still get grids on if the battery is still not warm. Weird setup if you ask me. Most likely driven by trying to meet idle emmissions at the time.

[s10010001]

I haven’t had a chane to hook the grids back up and measure ampreg draw but I just got done doing about 50 miles running around town, and I got to say, by simply unhook the grids the truck is running absolutely perfect. I have check ed the ac noise at several points in the last few days and it’s never been above .04. 

 

So if the running theory is the grids are kills the alternators, I must have in hooked mine just in time. 

[Mopar1973Man]

Grid heater logic is based on IAT and battery temperature. Strange but true I've seen it many many times where the IAT (fooled) is 143*F and the ECT is 190*F. In all theory there shouldn't be any grid heaters. This is partially true. The preheat is not present but the post heat is based on the battery temperature so even though the IAT is 143*F and ECT is >190*F you'll still get post heat because battery temperature is low. Where the break point is battery temperature I'm not sure but let assume 60*F outside. So this means if you start the engine and idle excessively like was doing where I'd sit in a parking lot waiting for MoparMom and getting cold in the cab I would fire up and get heat going again. So the grid heaters would bang away even with high idle going because the truck never moved and the battery temperature is low. Eventually the diodes overheat and "Presto" I've now got AC noise issue. 

 

Still in all I'm still having a hard time with this because all the years I've done this in the past and left the truck to warm up and 10 years gone by without an issue. Still leads me to the draw of the grid heaters are getting more as they age.  

[s10010001]

1 hour ago, Mopar1973Man said:

Still in all I'm still having a hard time with this because all the years I've done this in the past and left the truck to warm up and 10 years gone by without an issue. Still leads me to the draw of the grid heaters are getting more as they age.  

 

Makes sense for sure. Like its taking 10-15 years of use to see the grids start failing. Odd mine were acting up with >70k on the clock. It seems like it would be a "amount of use" thing, not age. I still need to check my amperage draw, I didn't get time this weekend. Id like to get it on video too so y'all can hear the whining noise it makes too. 

[dave110]

The battery temp sensor. What if that failed? The PCM uses it to tell the alt. how much to charge. What if it's failing and causing the PCM to think batteries are always cold therefore charging all the time and over heating the diodes? There's my brain storm for the day.

[Mopar1973Man]

20 minutes ago, dave110 said:

The battery temp sensor. What if that failed?

 

There would be a P1492 or P1493 for failed battery temp sensor.

 

23 minutes ago, dave110 said:

What if it's failing and causing the PCM to think batteries are always cold therefore charging all the time and over heating the diodes?

 

Not likely. The voltage band is 13.2 to 14.8 volts. So as the temperature goes up the voltage goes down. As the temperature goes down the voltage goes up. This can be verified by checking the charging voltage. If it's over 14.8 volts then there is an issue. 

 

A overcharged battery becomes gassy and stinks like sulfur. Not to mention the battery is prone to constant reloading of water because of the overcharging condition so battery lifespan is greatly reduced. 

[dave110]

OK. Just a thought.

[s10010001]

how should I check the grids amperage draw? I know how to use my clamp meter, just wondering from where? 

 

I hooked my grids back up the battery and my clamp over the positive lead coming form the battery. I put the key to on (WTS light came on), I could hear the grids click on. It was sorta jumping around all over the place but it wasn't very high, it was only like .10-.20 amps AC. That doesn't seem right at all. I hadn't started the truck yet this morning it was plenty cold. 

[dave110]

You are measuring DC amps, not AC. Does your  meter handle 200+ DC Amps? Many do not. I measured mine with an inductive ammeter and measured the wires going to the grids themselves.

[wh82]

For your original lock-up issue there's a post somewhere out there about moving your ground wire for the PCM, you'll definitely want to do that regardless of any alternator repairs. The reasoning behind it is Even though you have some AC ripple in your system (and you will always have SOME) the sensors (mainly the APPS for this issue) and computers run at either 3.3 or 5v which has been regulated down from 12v using the fluctuating ground reference but some of that is filtered by your batteries. And the regulator's ground reference of course changes with the computer's ground reference when regulating so its still a cleanish 5v.

 

Dodge did something really odd and ran this ground right across the alternator to the battery on the opposite side of the truck instead of to the closest battery. This causes your ground reference for the computer to be off because it picks up noise like an antenna being right on top of the alternator. Easiest thing is to undo the zip ties and a couple of bolts to give it some slack and run it across the top of the radiator support which will provide someone of a shield and increase distance. I did this when I was away from home without the proper tools to solve my problem (which was rapid lock-unlock while towing 7000 up a steep hill, it was scary loud clunking and jerking). When I got home, I cut that ground completely and put it into the battery terminal closest to it. I haven't had a lockup issue since. Later on I replaced my alternator with a 270XP (200A at idle) Since it's a high current alternator it actually has a little more ripple than stock but not bad enough to do any damage to anything.

 

I noticed in another thread you bought the Nations alternator you mentioned at the top of this one. just curious if it has any markings like the others I've seen that indicate the actual brand?

 

Update: Cant find the post I originally went off of but this guy's explanation is identical to what I did:

http://www.kentsoil.com/dodgebug1.htm

 

Edited February 26, 2018 by wh82
update

[s10010001]

1 hour ago, wh82 said:

I noticed in another thread you bought the Nations alternator you mentioned at the top of this one. just curious if it has any markings like the others I've seen that indicate the actual brand?

 

It’s a Denso Hairpin 180, says right on their site. 12pack

 

as for the ground wire, that’s just a bandaid

1 hour ago, dave110 said:

You are measuring DC amps, not AC. Does your  meter handle 200+ DC Amps? Many do not. I measured mine with an inductive ammeter and measured the wires going to the grids themselves.

 

Dou!!!! Pre coffee work is a big No no... 

 

i do understand the difference between ac an dc I promise  I am pretty sure I checked it in dc not ac, but my meter is silly how it flips to dc so maybe I wasn’t. It’s just a tiny little icon that says ac or dc. 

[wh82]

1 hour ago, s10010001 said:

It’s a Denso Hairpin 180, says right on their site. 12pack

 

as for the ground wire, that’s just a bandaid

Ah, got it, I missed that somewhere. I did see the pictures from the other Manufacturer on their site though so that's why I've been saying that.

 

The ground wire is and isn't a band-aid, agreed that its not the source of the issue, but you'll likely still get some inductance if the wire's right across the alternator, AC can jump wires so that wire laying there can POSSIBLY pick up noise pre-rectifier. Or maybe its even acting as a pick-up wire like all those wires inside the alternator. That's why I said it's still a good idea to move it. How often on other vehicles do you see wires that close to the alternator that aren't specifically for the alternator?

 

I just thought of a quick test, most people know to test alternator ripple just use your meter on AC across the battery terminals, but to see if this wire is indeed picking up noise aside from the diodes, put it on the 2 ground points 1 on the battery ground passenger side where this wire heads to and the other on the pcm ground while the wire still goes across the alternator...(with your brand new clean alternator) there's probably still AC there. All I know is moving it away fixed it for me.

 

I tend to re-do all grounds on all my vehicles, you'll find 0 guage wire and no braided straps anywhere on my truck, all soldered, no crimp-and-go and I removed that quick disconnect out of that particular ground cable and shortened it, the shorter the run for any electrical circuit the better. It's all time consuming but in my opinion, worth it.

Edited February 26, 2018 by wh82

[s10010001]

Ohh lookie what showed up! 

 

[Mopar1973Man]

4 hours ago, wh82 said:

The reasoning behind it is Even though you have some AC ripple in your system (and you will always have SOME) the sensors (mainly the APPS for this issue)

 

Actually its speed sensors. Like the transmission speed sensor which get corrupted by the AC noise. APPS sensor doesn't care about the AC noise really its just a 5V signal. Now things like the speed sensors that are hall effect sensors that create a AC sine wave then you inject a second AC sawtooth wave from the alternator now things get stupid fast. 

 

APPS sensor will fail from excess AC noise because of the logic chip can't handle the AC noise and fails. This why Timbo's APPS is the best solution being there is no electronics in the Timbo APPS.

 

There is an internet myth about APPS voltage and voltage adjustment then APPS sensor grounding etc. These don't fix anything and actually create more problems best to not do any of these mods!

[wh82]

1 hour ago, Mopar1973Man said:

 

Actually its speed sensors. Like the transmission speed sensor which get corrupted by the AC noise. APPS sensor doesn't care about the AC noise really its just a 5V signal.

5V Signal yes, analog, a really fancy variable resistor. and its going to be relative to the computer. Regardless of which sensor, I'm sure the computer takes into account multiple at the same time. (Dodge does recommend the alternator and APPS when having this issue) your computer needs a strong ground, the electrical systems on our vehicles float. So the ground needs to be a strong reference to the battery negative. The battery provides the reference for the entire vehicle, if left to the alternator it wouldn't be stable as the battery provides the capacitance needed to smooth it all out. To get this everything needs to have clean, electrically strong grounds, battery to chassis, chassis to engine, engine to battery. If done wrong you'll still have a difference in potential and a ground loop which causes noise as well.

 

This is like any other logic circuit and needs a strong ground reference and all things communicating need to have the same reference, that cable running across the alternator can pick up stray voltage changing that reference so on the up swing of any waveform the voltage would appear to drop on a sensor that has a strong un-interfered with reference to the battery. causing the voltage to appear to dip to the computer. For example you get 1v p-p AC on that line, your computer would vary up and down from 4.5 to 5.5v. Now the computer may or may not see it that way as the regulator for 5 volt floats on that ground wire in question and there's enough head room to the 12/14v but other things connected would suddenly be seeing this variation unless they are powered from and floating on that same regulator for the computer, ground and all. so if the APPS doesn't share a ground the equivalent would be stomping and releasing the pedal quickly and it not knowing what you want.

 

During my personal lock up issues I saw the TPS (APPS) reading on my scan gauge jumping around like it couldn't read the APPS so I believe this to be true. My original issue with this occurred when my alternator was still OK with no AC ripple at all it barely started getting some almost a year later and I replaced it just because I was adding on my usual mix of equipment I knew that the stock could not handle. My APPS is the same one that was in use but I could see the change in the readings immediately upon moving that cable.

 

The more load you put on the alternator or even the faster you spin it along with your engine, the more possibility for the noise to be inducted into that wire, so I'll respectfully disagree since I know you know a lot about these vehicles but I believe that that wire should be nowhere near the alternator and not even run across the engine at all. That's why I moved it to the driver side battery directly. The other weak point is that clip connector that's there, if that gets even a bit corroded, your ground strength will be lessened, and more prone to picking up these voltage fluctuations from the alternator.

 

Too many years of excessive Stereo (SQ competitions) and Radio gear in my vehicles (Ham, CB, Commercial etc...) I've had ground loops, fuel pump noise, alternator noise, the works, RF and Audio amplifiers are really sensitive to noise. I'm not an EE (too much math) I'm not making this up either, was a firmware developer and test engineer for a really long time. Too much time debugging hardware and logic circuits.

 

Wow, sorry everyone for the long winded reply.

 

Edited February 27, 2018 by wh82

[Mopar1973Man]

Here is where my view comes from... This is common to all electronic vehicles just every one of them exhibits the signs differently.

 

Also, remember ground doesn't mean AC noise cancelled. You can produce AC waveforms on a negative side or ground as well. 

Edited February 27, 2018 by Mopar1973Man

[wh82]

31 minutes ago, Mopar1973Man said:

Here is where my view comes from... This is common to all electronic vehicles just every one of them exhibits the signs differently.

I absolutely agree with the video on a failed diode. What I've been trying to say is you can get alternator noise without a failed diode. When I had the lockup issue I had minimal ripple, almost none. This ground mod fixed it for me and apparently others. Some may never see an issue. I'd rather make that wire more efficient than risk it. So I thought I'd offer it again for those who want to try it.

31 minutes ago, Mopar1973Man said:

Also, remember ground doesn't mean AC noise cancelled. You can produce AC waveforms on a negative side or ground as well. 

Exactly, but a failing ground connection will make AC noise easier to pick up... Especially when running right over a noise producing device... (Alternator) Of course in true AC there is no ground... in this case its a ground wire that would possibly pick up noise, failed diode or not.

If the connection to the battery is solid, that waveform will tend to flow across the battery and get filtered a little, not necessarily cancelled but its got nowhere to push past the battery when its just noise vs when a diode fails the whole system sees the wave because the circuit is complete.

But if that connection is bad, that noise will go to the computer and mess with it instead. Path of least resistance.

We are kind of saying the same things in respect to the failed diodes.

 

 

 

Edited February 27, 2018 by wh82

[Mopar1973Man]

You need to meet @W-T you both are a two peas in a pod. He's also another that is critical about the grounds he's also got a long post going on how he's reworking the master ground for the PCM, ECM and VP44. 

[Marcus2000monster]

1 minute ago, Mopar1973Man said:

You need to meet @W-T you both are a two peas in a pod. He's also another that is critical about the grounds he's also got a long post going on how he's reworking the master ground for the PCM, ECM and VP44. 

Do you have a link to the thread ?

[Mopar1973Man]