W-T ground mod

[Dieselfuture]

16 hours ago, dripley said:

Just remeber the solder and the wire most get hot for the solder to bond properly. Just melting the solder is not enough.

Flux is important for bonding too

[dripley]

Very true. I left that part out. I put flux in the terminal and shoved the expose wire into the flux also.

[Alexio Auditore]

For the charge wire, if I upgrade to a 180 nation's amp, should I use a 4awg or 2awg? Forced to do this now that alternator is pushing higher ac, and the case where it bolts to the bracket has worn a hole through it.  .08 ac noise currently. I may do the mod, then check with the old alternator to see how much ac noise dropped, the put nations on.

[IBMobile]

23 minutes ago, Alexio Auditore said:

For the charge wire, if I upgrade to a 180 nation's amp, should I use a 4awg or 2awg?

The distance from the alternator to the right battery with a circuit breaker/fuse in line is just over 24" ( 2' );  4 awg will carry 180 amps 72" ( 6' ) safely.

[Alexio Auditore]

On 12/10/2019 at 7:52 PM, JAG1 said:

I had the same thing happen and never ever saw an alternator smokin so bad. I did not ruin my PCM for some reason, yet it was hot enough to start a fire.

 

Since there is no temperature sensor on the passenger battery with the B+ charge wire connected there, after doing the W-T grounding mods, the pcm cannot limit the voltage based on temperature, Therefore could fry the alternator while attempting to charge older batteries with a bad cell. I need to either move the temperature sensor to the passenger battery or place the B+ wire over to the drivers battery. Or you can do the additional 4 wire battery to battery parallel that WT wants for correct battery sensing and avoid this problem. I say this because a lot of us have done the W-T mods, but have not completed the 4 wire battery parallel wiring.

 

Believe me you do not want to fry an alternator and your PCM only to find it was older batteries that may cook may not cook everything.

 

I say check your batteries too Mike  as I learned this from W-T while on the phone with him.

This is from the pcm failure thread, talking about installing a 7.5 amp fuse on the blue wire for protection of pcm. Glad I saw this, ill throw that in while I'm at it. But I have a concern to what JAG1 has mentioned above. 

 

I'm am about to do this mod tomorrow, but reading this makes me reconsider the charge wire from alternator to aux. battery. Without strapping 4 more cables across your truck, or moving the battery temp sensor to auxiliary battery, is it better to just run the charge wire over to the driver battery with the inline fuse? 180amp nations alternator On the way, 200amp fuse.

 

I wouldn't want to have the alternator overheat like mentioned in the quoted text because of a bad battery.

Re-reading some of @W-T information on page 2 of his article mentions the importance of at least adding another ground cable between both batteries since it is now charging the auxiliary first, especially with a bigger alternator installed. 

What size wire would be good?

[dripley]

2 hours ago, Alexio Auditore said:

This is from the pcm failure thread, talking about installing a 7.5 amp fuse on the blue wire for protection of pcm. Glad I saw this, ill throw that in while I'm at it. But I have a concern to what JAG1 has mentioned above. 

 

I'm am about to do this mod tomorrow, but reading this makes me reconsider the charge wire from alternator to aux. battery. Without strapping 4 more cables across your truck, or moving the battery temp sensor to auxiliary battery, is it better to just run the charge wire over to the driver battery with the inline fuse? 180amp nations alternator On the way, 200amp fuse.

 

I wouldn't want to have the alternator overheat like mentioned in the quoted text because of a bad battery.

Re-reading some of @W-T information on page 2 of his article mentions the importance of at least adding another ground cable between both batteries since it is now charging the auxiliary first, especially with a bigger alternator installed. 

What size wire would be good?

My experience doing this mod was very good. Prior to it the batteries would be slightly moist on top, not always but maybe 60% of time. This would cause the corrosion on the terminals also if I did'nt  put some motor oil on them. This was on the factory set up. Since I did the mod with the charge wire on the aux battery they have remained dry 95% of the 2.5 years since I did it. And to this day Inhave put nothing on  my terminals and they are corrosion free. I am going to see how long they go. The other benefit is the ac voltage drop I saw was from .035 to .010. I cant why batteries are less gassy from the mod I just know that the system seems happy with it.

 I ran a #4 wire between the negative posts on the battery with a stock alternator. But you could as big a wire as you want but you dont need any bigger cable than your + is. WT ran a lot big wire on connecting the batteries together on his but if you look at the electrical demand he puts on his truck,  I can understand  why. Now if l had to explain the why's and whefore's of all of this, I cant. I just know it works well on my truck. Details l will leave to the more electrically educated here. 

[Alexio Auditore]

Ok. I bought a 1/0 cable to run negative to negative..(apparently no 0 guage? Electrical incompetence is showing  here)

 

if I did add an extra positive, should it be the same size as the one currently going across?

 

I've been working myself up for a year to do this, been practicing my soldering and crimping skills(harbor freight hydraulic crimp is pretty awesome btw.)

 

When I read through this again last night I discovered the fuse protection for pcm, but also saw the caution of running a charge wire to auxiliary battery when it doesnt have the temp sensor for added protection. I just don't want something bad to happen, which is kinda why I thought of maybe running the new charge cable directly to the passenger battery. 

I'm probably over thinking this, but my electrical experience and confidence is small, so I just want to be smart and careful.

Edited May 28, 2020 by Alexio Auditore
Give update, correcting terminology used

[Mopar1973Man]

Over thinking for sure.

 

Negative cables should be as short as possible to the block not battery to battery. The block is much better bridge than long cable.

 

Battery temp sensor works fine like it is only if both batteries and cables are in good order. The voltage should be the same. Its when the cables and batteries are failing will you see issues. Like myself still have factory cables and only my second set of batteries.

 

Computer wise the W-T ground mod shrinks the ground cables shorter and reducing voltage loss in travel to ground. This cuts off 4 feet of cable and get ground fast from the block on large gauge cable than an extra 4 feet. Then it doesn't help having an AC rich alternator charge lead running parallel to the master ground cable for both the VP44 and ECM. After the W-T ground mod the AC noise will be null 10mV AC on average.

[Alexio Auditore]

2 hours ago, Mopar1973Man said:

 

Computer wise the W-T ground mod shrinks the ground cables shorter and reducing voltage loss in travel to ground. This cuts off 4 feet of cable and get ground fast from the block on large gauge cable than an extra 4 feet. Then it doesn't help having an AC rich alternator charge lead running parallel to the master ground cable for both the VP44 and ECM. After the W-T ground mod the AC noise will be null 10mV AC on average.

Even to me, this makes sense. Stupid design on dodges part...but.

 

I thought running the extra cable battery to battery helps balance the charge between the 2, keeping them parallel, since the charge cable is now to the auxiliary battery? 

 

This is my understanding: you do this in the absence of a temp sensor on the passenger battery because you have the charge wire now going to said battery, so that in the case of a bad, failing auxiliary battery, the extra cables you ran between the 2 batteries keeps them charging roughly the same, balanced, and as the one heats up, the other should too(letting the one with the sensor detect the rise in heat) to at least let you know you have a issue and not over work and fry your alternator and PCM. which is what i believe @JAG1 was pointing out, and experienced too. 

 

Again, this is what I'm understanding, it makes sense, but I wouldn't doubt if im wrong somewhere, again im not a electrical savvy person. (I literally have read and re read the wt mod and this thread over and over just to understand it, even though it is relatively simple.) I want to just make sure to do this right, with the added protection of a more likely  "what if" situation, like the pcm fuse install(not that you can predict all "what ifs")

Most everything is still stock on my truck, battery cables and all, still looking in good shape 

 

I'll still be running the 6 gauge ground from driver battery to block where the wt mod pointed out.

[Alexio Auditore]

Quick question: the wire running from driver positive battery terminal to the pdc, do we disconnect it or leave it? Do we leave the fuse in there as well?

Edited June 4, 2020 by Alexio Auditore
Added picture

[dripley]

Yes. It is needed to power the PDC. My fuse is still there also.

[Alexio Auditore]

Thanks dripley. Thought I'd just give my experience so far. I did the extra ground strap, turned out pretty clean and nice. Used clips to hold the new cable along the same route the positive cable went. Crimped, soldered, and heat shrinked the ends.

 

Sexy! ?

That was yesterday. Today, I got around to changing the charge cable, moving it to the auxilary battery. Here is the before numbers on the ac noise....

With electronics, lights, and heater off....

With lights, radio, ac full blast on, all after driving around. I want to say that these numbers are lower than what i first recorded a few days ago, it was closer to .073. This reading above is with the new battery ground strap 1/0.(maybe it helped lower the ac noise as well? Who knows, couldve just been happenstance.)

 

And here is after re-routing the charge cable to the auxiliary battery, through a 200 amp fuse.

With everything off.....

With everything on! After a drive to bring up to operating temp. Highest reading was .045. What a difference for sure. I still have to do the w-t mod for the grounds and rip out the old charging wire. But so far, so good. I still have to heat shrink the charge wire, the parts store gave me heat shrink that was waaaaayy bigger than 4 guage cable, saying it would would shrink. It did, but not nicely or tightly on the ends. 

I would like to get a water proof fuse holder, I haven't come across one yet. I used a 2.5 x5 inch aluminum plate to hold the fuse holder to the battery tray.....holder.....hmmmm...

This took a lot for me to work myself up to it, and it seriously has been pretty easy and straight forward. I made sure to practice some soldering with extra wire and lugs, and also a couple practice crimps. The wires aren't going anywhere...

Next is the important grounding fix and the nations 180amp alternator!

 

By the way, is there something you guys would recommend putting on the copper lugs to prevent corrosion?

Edited June 4, 2020 by Alexio Auditore

[tmaxxs10]

Could you just add a 2nd battery temp sensor to passenger side and splice into driver side wire? Or does it work in resistance and that woyld throw it off? 

[dripley]

On 6/4/2020 at 1:29 AM, Alexio Auditore said:

By the way, is there something you guys would recommend putting on the copper lugs to prevent corrosion?

A little motor oil will do the trick.

I did the right after WT wrote the article and have no corrosion what so ever. I also have applied nothing to the terminals. They are as dry as the day I did the mod. Prior to the mod the batteries would get a little gassy sometimes and corrosion would start, post mod the charging system seems very happy and no gassy batteries.

[Mopar1973Man]

@JAG1

 

Just to show there is ZERO difference. Using my jumper cable between both batteries on the negative posts using BOTH leads to give MAX gauge size.

 

Still only 4mV drop between NO GAINS! Again this is NOT REQUIRED and not going to gain you anything... No reduction in AC noise or any improvement for voltage drop.

[Mopar1973Man]

 

The reason this is not required is the simple fact of electricity wants to take the path of least resistance. Being that both battery are grounded to the block and frame there is going to be ZERO amp flow between batteries on the new jumper cable as long as the factory grounds are in good condition.  Since all the electric stuff grounds to the body, frame, etc. The electricity will flow from the batteries into the frame or body. 

 

The only reason there would be any flow on that bridge wire between batteries is the fact one of the ground leads to the block or body has failed so the flow would start because of a bad ground cable. Now say the passenger side is 0.3 volt drop on the master cable now that bridge cable would make up that 0.3 Volts. This will mask the fact you now lost a passenger side master ground to the block. Now this is why I said do not do this mod because it will mask the failure of the block and body ground and increase the failure rate on the existing cable dumping more load and amperage on the remaining ground cable. Fix the factory cables if your seeing more than 0.2 Volt drop.  Best to leave the battery to battery jumper cable out. This way when a ground cable fails its going to show up as a weakened battery on one side because of the bad cable. Very easy to test for like shown above. My cables are 18 years old and still only a 3 to 4 mV DC drop.

 

@JAG1 in your case your passenger battery had a shorted cell and the charging system kept dumping power at a failed battery. The battery was charging but dumping lots of heat in that failed battery. Just like a failed cable you can feel the cable is will turn hot where it failed especially on these engines being the starter draws quite a bit amperage. This was not because the battery temp sensor wasn't on the passenger side. It not because of the ground cable. Simply put it was the failure of the battery and shorted plate. 

 

Just like I tell people not to add ground to APPS sensor, or add noise filters on the PCM for AC noise. All you doing is masking the AC noise problem and ground issue. Being W-T figured out the shorten the ECM and VP44 ground to the gear case that is a bonus being you now cut out over 4 feet of cable. Short length grounds are always best. Then the simple fact of the charge lead and ECM / VP44 ground running criss crossed ground and charge lead this was a absolute bonus to remove the noise issues. 

 

Edited July 23, 2020 by Mopar1973Man

[Alexio Auditore]

Question from a electrical dummy. If the charge cable was still on the driver battery, but the shorted cell was on the passenger, wouldn't the driver battery heat up also because the passenger side is still getting juice dumped into it, but it goes through the driver side battery first? So as the driver side heats up, the temp sensor will detect it?  

[Mopar1973Man]

No. Won't matter. Does not change the voltage. This is because there is only X mV drop from battery to battery. Just probe the batteries while running it will measure the same. If not you cable has a bad spot and voltage drop is occurring. Just need to replace the bad cable.

[Alexio Auditore]

Ok. So what I'm understanding is that your battery temp sensor is worthless half the time? If the passenger battery fails on any scenario, better pray you notice it before it and your alternator get super hot and either fail completely or catch on fire? 

[Tractorman]

2 hours ago, Alexio Auditore said:

So what I'm understanding is that your battery temp sensor is worthless half the time?

 

The battery temperature sensor has only one purpose.  It is to sense the overall temperature of the battery under normal operating conditions.  It does not monitor temperature to correct problems, nor does it fix anything.

 

It is placed in the tray of one battery (does not matter which one) so that a stable temperature wil be recorded and be directed to the PCM.  If the ambient air temperature is 100 degrees, the battery temperature will sense this and send a message to the PCM.  The PCM will reduce the alternator output upper limit voltage to - say to 13.8 volts, just guessing - so that the batteries don't gas excessively and over heat.  Just the opposite, if the ambient temperature was 10 degrees, then the battery temperature sensor will send a different message to the PCM.  The PCM will increase the alternator output upper limit - say to 14.2 volts, again just guessing, to compensate for the cold temperature.  The PCM is constantly monitoring the battery temperature sensor (and battery voltage) and continually tells the alternator what to do - so, the battery temperature sensor makes batteries last longer under all types of driving conditions and it is working all of the time.

 

- John