Battery Temp Sensor question

[dripley]

[Tractorman]

You guys and your popcorn....,

 

- John

[Mopar1973Man]

20 hours ago, JAG1 said:

 @Mopar1973ManA good voltage regulator could protect the alternator and the PCM. Did you ever learn what shorted out your alternator Mike? Was it those 4 lights?

 

My alternator shorted out on the blue wire side. This was enough circuit to burn a hole through my PCM and never blow the 20 Amp fuse that protects the PCM. All I can say that alternator had a short on the blue wire side. Last alternator I had rebuilt was good but the brushes was fried and had alternator shop replace them for $40 bucks. This last alternator I don't think had any problem but time was short I needed my truck and replace it to find the problem came back and was the PCM protection fuse fell out. So, technically I've not had a alternator failure really since the W-T ground wire mod.

[JAG1]

Thanks Mike . Did you ever take that Alt. apart to find where the problem was with the blue wire in there?

 

I am very much interested in finding what's causing lots of these Alts to get so hot you can't touch them. In Googling a search you find quite a few that have cooked their Alts, but no indication of what's causing it.

 

I am going to invest time into looking at my starter motor cables and anything that might have rubbed to cause full sink and make a fuse stud bolt glow like that. Remember I had not started the engine, only turned the key on when the bolt glowed. luckily I had the hood open and the fuse holder up high able see it. I suspect it's still the grid heater relays somehow sticking, maybe one stuck on while the other just clicked in and so both grids running at the same time could have done that.

 

Just looking  closely at the contacts inside the old relays may be a clue as the copper looks like is splayed outward like it was melted a bit around the wear marks. It's hard to know for sure. I need to use the magnifier which might help. Also I have always had my grids disconnected thanks to Mopar1973Mans advice, except on these two mornings of which the second one was the glow bolt morning. Wonderful with coffee on a Saturday . Reason my hood was open was the burning electrical smell the day before and the earlier episode with the cooked boiled fried alt. only two mos. before.

 

I found the 12 inch piece of wire that had the glowing bolt thru its lug and will do a voltage drop test on that and the other fuse holder installed to the other second gen truck. 

 

I also found that it was operators error on the use of the Fluke meter. I was using the wrong scale, had the decimal point in the wrong location which caused it to try reading small fractions and bouncing all over with small fractions of ohms resistance. Retesting both Alts. that were pulled shows they are not crossing B+ stud to the frame housing .

 

Sorry for the long post as this is an education for me thanks all of you and one very drilling/ lecturing buddy down in Ca.      

Edited February 8, 2021 by JAG1

[Mopar1973Man]

1 minute ago, JAG1 said:

Did you ever take that Alt. apart to find where the problem was with the blue wire in there?

No. Because I was stuck in Ontario at night without a alternator so I cored it out and had it test it failed completely as for what I have no idea since I wan in Ontario and no time to pull it a part in a parking lot with limited tools and knowing my PCM was fried at that point it was done.

 

Still in all... If you short the green wire to ground you get a runaway alternator that is overcharging. No damage to the PCM will occur. Now short the blue wire to ground and PCM will fry. 

3 minutes ago, JAG1 said:

am very much interested in finding what's causing lots of these Alts to get so hot you can't touch them.

 

Heat is a sign of high electrical loads. First place to start. Also sign the batteries and/or cables are not up to the task.Weak batteries or shorted cell battery will still cause the alternator to get hot. Just like my landlord at my second shop he was using his winch for long periods with bad batteries and blew the alternator fuse. Again the alternator is not suppose to hold all the heavy electrical loads, that is the batteries job but if the batteries are not up to the task then its handed off to the alternator and in turn shows up as heat. As the load continues the alternator burns up brushes and/or didoes. So far I've never seen winding burn...

 

7 minutes ago, JAG1 said:

I found the 12 inch piece of wire that had the glowing bolt thru its lug and will do a voltage drop test on that and the other fuse holder installed to the other second gen truck.

Here again that glowing bolt is a sign of poor connection again points back to what I said of poor cabling or connections. You could of seen this using the voltage drop test and would of been high volt number there. I'm sure higher than 0.2 volt drop.

 

Remember this same test can be uses on "ALL WIRING" of any vehicle right down to small engines like motorcycles and all the way to semi-trucks. It can be used on any circuit to measure voltage loss as the circuit is running. Optimally you want ZERO voltage drop. Less is better but in the article it calls 0.2 volt drop a fail for starting cables.

Now a example of this in action. I had a 1982 Honda Sabre 750cc V4 motorcycle the cluster was semi-digital. When I was riding at night and using my head light and fog lamp (up graded to 100w)  both the cluster would spit out weird things at times. This point out I've overloaded the stock ground with the added wattage of the fog lamp. Come to find out the master ground for that motorcycle was under the fuel tank and was only a 16 gauge wire. Only ONE ground. After measuring I was getting 0.3 volt drop on the ground circuit. I added one extra ground up by the headlight and fog light to aid in this voltage drop afterwards drop 5 to 6 mV DC. 

 

As you see... That was a change I made to improve light which came at the cost of overloading the master ground after allowing for a extra ground problem was gone. Now using this information this is why on my truck I went the other direction and REDUCED the electrical loads and now gaining ground and not having the alternator issues like I did. I've double and triple check this on at least THREE different trucks. I know the W-T ground mod does work! As for the parallel ground does not gain anything in the THREE othere truck I've try it on. People tend to forget I'm not just working on my truck and testing but working with many owner and trucks and seeing if there is any change. As for the parallel ground it OPTIONAL in my mind and going to do anything for ground performance. Being all them resulted with and without parallel ground in the 2 to 8mV drop that doesn't change on good master ground cables. 

 

I can see it for W-T when hes got linear, ham radio and high current draw with a need for absolutely CLEAN POWER. Any noise is brought back to the radio as frequency noise in the back ground. Hence why he's done noise mods to his AirDog pump to cut out the RF transmission from sparks created at the armature of the pump. 

[JAG1]

@Mopar1973Man where does the grid heater trigger wires come from? Are the relays controlled by the ECM or is it the PCM? Thanks Mike or anyone 

[Mopar1973Man]

Comes from the ECM. You see the ground is supplied by the body ground and the ECM controls the +12V to the relays.

 

[JAG1]

@Mopar1973ManIs this another source of potential damage to the ECM, needing protection diodes?

[Mopar1973Man]

No, as long as you buying the stock OEM relay made for the truck. They are design to do this job for years. Personally I fire up and get moving as soon as possible. There is nothing worse that starting a truck leaving to idle at 800 RPM having the grid heater clicking on and off to heat the manifold drawing more power than the alternator can produce at 800 RPM. 

 

Like I said I typically unhook the grid heater in April and leave it unhooked till October. All this time the relays can do what they want but no power present. 

 

But yes starting and leaving it idle 800 RPMs is the absolutely worst thing you can do to the alternator on a cold start. If you had either my high idle kit or the Quadzilla where you can high idle now at 1,200 RPM now the alternator can handle the loads between being it like being driven 20 to 25 MPH and the alternator can cool the diodes because of extra fan speed in the alternator. Back to the batteries if they are weak every time the grid heaters heat then the load majority on the alternator since weak battery normally won't carry much of any loads. Again now you end up with a hot alternator attempting to burn up the diodes. 

[LorenS]

3 hours ago, Mopar1973Man said:

or the Quadzilla where you can high idle now at 1,200 RPM now the alternator can handle the loads

1. I have my Adrenaline set to hit high idle at 30 seconds.  Is this a reasonable time?
2. Is the high idle supposed to engage with the truck in gear and foot on brake?  That was surprise at a stop light yesterday morning!
3. How long should it take to reach the 1200 RPM?  I notice mine jumps really fast to around 1000 RPM then wavers up and down as it slowly increases idle speed to 1200 RPM.  Is this normal?  Fuel pressure is ~18 PSI the whole time.  This happens whether it's 50 degrees or 5 degrees outdoors.
4. It just occurred to me the up and down idle speed may be related to the grid heaters drawing power and pulling down the engine.  Is THAT normal?  It's not a matter of a couple of seconds, it's like 5-10 before it creeps back up.

This occurs even with my truck plugged in for 3 hours.

 

@Quadzilla Power 

[Mopar1973Man]

40 minutes ago, LorenS said:

I have my Adrenaline set to hit high idle at 30 seconds.  Is this a reasonable time?

Yes that is good. I'm set to the same time delay.

41 minutes ago, LorenS said:

Is the high idle supposed to engage with the truck in gear and foot on brake?  That was surprise at a stop light yesterday morning!

Quadzilla yes. Cummins ECM No. The ECM software will cancel if you touch the brakes.

 

42 minutes ago, LorenS said:

How long should it take to reach the 1200 RPM?  I notice mine jumps really fast to around 1000 RPM then wavers up and down as it slowly increases idle speed to 1200 RPM.  Is this normal?  Fuel pressure is ~18 PSI the whole time.  This happens whether it's 50 degrees or 5 degrees outdoors.

Usually as the time runs out mine snaps instantly to 1000 to1200 RPM. On cold morning it might hang a bit low hanging at 1000 to 1100 RPM it not set by RPM on the Quadzilla but rough fuel amount.

 

43 minutes ago, LorenS said:

It just occurred to me the up and down idle speed may be related to the grid heaters drawing power and pulling down the engine.  Is THAT normal?  It's not a matter of a couple of seconds, it's like 5-10 before it creeps back up.

Yeah. That normal as the grid heater fires it drawing roughly 95 Amp and with cold start and batteries needing charged the alternator is most likely maxed out hence why when the grid hit the volt needle falls a bit.