Ok Gang...I've got a for sure way to diagnose torque converter lock up issues where it lock and unlocks at about 45-50 MPH. I had a gent call me yesterday with this problem and he's replace both batteries, alternator and the APPS sensor. Attempted all the different wiring issues (adding ground, tinfoil etc.) nothing worked. Like I told him the truck ran 11 years without all this stuff and doesn't require any wiring change to make it work. What it needs is the damaged part to be replaced. So he's returned the wiring back to stock setup.Now I told him to unhook the alternator fuse and take it for a ride... Guess what... No problems! Even though he replaced the alternator it has a damaged diode in it and it bleeding AC noise into the electrical system.So before doing any wiring mods, tinfoil, adding grounds, adding filter... PLEASE! Bench test your alternator! This is the second time I've suggested this and both time resolved the torque converter lock up issue.

Hang on a sec. You are break out of the 2nd generation. Now why is it that I've got a 20 year old 2nd Gen without kind of torque convert lock up issues? Why is it that most of these trucks in the 2nd gen bracket went at least 10 years without a problem? So my question is what failed?

It more of the fact of return back to the state it was designed and working not band-aiding over a issues. Like the standard noise filters, tin foil, and extra grounds. These trucks can be repair back to working state without modification.

2 hours ago, Mopar1973Man said:

Hang on a sec. You are break out of the 2nd generation. Now why is it that I've got a 20 year old 2nd Gen without kind of torque convert lock up issues? Why is it that most of these trucks in the 2nd gen bracket went at least 10 years without a problem? So my question is what failed?

It more of the fact of return back to the state it was designed and working not band-aiding over a issues. Like the standard noise filters, tin foil, and extra grounds. These trucks can be repair back to working state without modification.

You are right Michael as usual with your common sense logic.  My own personal opinion is that it is the ground corrosion and perhaps some connector pin and socket corrosion that is appearing on these old trucks.  It is easier to mask the problem with filters (or separate grounds) than it is to dig in and find the real actual cause. I would want a oscilloscope to find it and how many mechanics would have a lab quality scope? They  do have some specialized scopes but they are not general purpose differential input lab scopes required to trace it down to a particular ground connection.  Mopar made a mistake in  not  going to differential inputs until 4th gen.  My career job as an electrical engineer was control of industrial boilers, paper machines,  turbo generators etc. and we always used 4-20 ma loops to/from the computer for the I/O. Inputs always had a 250 ohm resistor so you got 1 to 5 volts at the differential input amplifier.   Zero volts meant an open circuit. Just about fool proof but expensive.  Optical isolators on input amplifiers meant you could withstand thousands of volts difference in ground potential when a substation transformer blew up and automatically shut down the chemical recovery boiler safely on UPS power. A truck has nowhere near the physical distance and therefore potential difference in grounds but it does justify differential amplifiers to cancel out common mode ground noise.

Edited December 28, 20159 yr by balsip

Okay so more testing, I found another dvm and it is reading between .012- .018 AC so that seems acceptable. After some more searching I found a wiring diagram posted by Mopar1973man showing the apps, map and oil pressure, plus some others all going to an s165 ground junction. I've looked and can't seem to find it, from what I've found its most likely in the loom by the ecm. I pulled some of the convering off but still don't see it, so I'm going to add a new ground to the blk/ltblu wire and see what that does. 

27 minutes ago, kc8ksg said:

Okay so more testing, I found another dvm and it is reading between .012- .018 AC so that seems acceptable. After some more searching I found a wiring diagram posted by Mopar1973man showing the apps, map and oil pressure, plus some others all going to an s165 ground junction. I've looked and can't seem to find it, from what I've found its most likely in the loom by the ecm. I pulled some of the convering off but still don't see it, so I'm going to add a new ground to the blk/ltblu wire and see what that does. 

I went to 1999 FSM  .pdf    from downloads section and did an Adobe EDIT +  "FIND"  on "S165". It  gave this:

"S165 (Diesel) Engine Harness, Near Engine Control Module N/S" on page 8W-95-2, so I am guessing it is a ground wire on one of the bolts holding the ECM  to the block.  Could always take   bolt out, wire brush it, put on  dielectric grease and tighten back up. Block threads tend to rust with age.

I asked a Dodge dealer mechanic whether he removes the fuel filter when changing the ECM.  He said  "No, makes too much mess with diesel all over the floor. I just get down in there."  Perhaps he hangs his ankles from the ceiling?

Edited December 28, 20159 yr by balsip

I could not find any grounds on the ecm, all the blk/ltblue wires went into the loom but I couldn't find where they all went together without unhooking the harness from the ecm and unbolting it from the block. 

I tapped the blk/ltblu wire going to the apps and took a test drive and NO MORE PROBLEMS! 

No more tc/od issues, map codes or oil pressure dropping. I came back and soldered it and taped it up, drove it about 50 miles with no problems at all. 

I realize it wasn't a perfect fix as I still have a bad connection at that junction but the truck is at least drivable now. If the problem arises again at least I'll have an idea where to go.

One other thing, the black/tan ground that goes from the passenger battery that everyone foils/moves, where does it go? 

I read it is supposed to be an ecm ground but never found the other end of it in the loom, I could have missed it though is it's not easy to see down there. 

 

Thanks again for all the help from everyone! 

Ok i finally got the chance go have the alternator tested again.. I took it to a 30+ yr local automotive specific electronic shop. The owner put it on his tester and tested specifically for diode issues and said the alternator is fine, no diode issues.. So now i dont know what my next step is, ALL grounds are clean, batteries are perfect, terminals look new, tps is calibrated proberly... Yet still acts up.. Its not every day but atleast a few times throughout the week.

There is an intermittent and loose connection somewhere, something backfeeding into the system (any loops of aftermaket wiring near a relay?) or something intermittently failing due to temperature.  As for finding it... that is going to be very tough.  

I wish there was a simple brute force fix, but other than going to a manual valve body, I really don't know!  Even then though, it wouldn't control lockup.

Edited December 29, 20159 yr by CSM

I finally found the solution to all our problems!!!  6 speed manual tranny.

http://rs130.pbsrc.com/albums/p280/zerglin/Smileys/Bonk.gif~c200

Edited December 29, 20159 yr by deej

3 hours ago, kc8ksg said:

I could not find any grounds on the ecm, all the blk/ltblue wires went into the loom but I couldn't find where they all went together without unhooking the harness from the ecm and unbolting it from the block. 

I tapped the blk/ltblu wire going to the apps and took a test drive and NO MORE PROBLEMS! 

No more tc/od issues, map codes or oil pressure dropping. I came back and soldered it and taped it up, drove it about 50 miles with no problems at all. 

I realize it wasn't a perfect fix as I still have a bad connection at that junction but the truck is at least drivable now. If the problem arises again at least I'll have an idea where to go.

One other thing, the black/tan ground that goes from the passenger battery that everyone foils/moves, where does it go? 

I read it is supposed to be an ecm ground but never found the other end of it in the loom, I could have missed it though is it's not easy to see down there. 

 

Thanks again for all the help from everyone! 

I think you have really found something that is very important.   I am starting to think that splice S165  is hidden under the black plastic loom near ECM connector and somehow has lost its ground tie to the block/negative battery?   Many people get this problem and it may be because this splice is just a crimped connection (prone to corrosion) hidden from our eyes by the plastic loom bundle? There are many many posts on finding S165 in other forums but no one actual seems to have found it or shown a picture. They seem to find black/lite blue tracer wire at a sensor and reground it and problem gone like yourself.  Must be a mother to unwrap the loom and find it? The 2003 CR trucks have a Figure to give a physical location but our FSM has N/S for "Not Shown". Mopar1973Man wiring diagram says "Near breakout for ECM " for S165 below so I think that is where we unwrap it.  I would take that as in the bigger bundle before the ECM breakout and it is probably a crimp jobber prone to the corrosion of winter salt spray.

Edited December 29, 20159 yr by balsip

ECM, PCM and VP44 ground...

G115 ground wire above and the wiring diagram below...

 

50 minutes ago, Mopar1973Man said:

ECM, PCM and VP44 ground...

G115 ground wire above and the wiring diagram below...

 

Michael, S165 is hidden in the loom. Read above.

KC8KSG  has made quite a discovery in my mind.

That's easy just ohm out the sensors back to the ECM. If you got 5 ohms or more from all sensors then I would say the S165 would be bad. Then again if the sensor signal ground is weak then the voltage would be high and you would have a entire series of hi volt codes or rather strange sensors reading across the board. So I would be just checking with a ohm meter from sensor plug to ECM plug to verify the wiring since its all 5 volt system and low current.

I have a spare wiring harness. Maybe I can try and track down the splice after work tomorrow.

When I tested my grounds they all came back fine with the tester not showing ohms, just going back to the blank screen with the - that it was making contact. I tried very hard to get the truck to act up in the shop and it wouldn't do it, reving, on jack stands in gear, even holding the brakes to get it to sort of "load" the engine. Nothing made it act up until I got it on the road and you could tell it wasn't fixed before it left first gear. 

Now here is my theory, right or wrong. S165 is somewhere in the ball of wires right out of the ecm, that spot lays on the engine mount. In my case  I think the engine rocking when under load is just enough to mess with that bad connection and make it rare it's head. 

It would also help explain why when it would take fits and run it's worst my oil pressure would act up and I got the map code, and when hauling a load it seemed worse, but I thought that was my imagination. 

 

Mike,  thanks for your wiring diagram, I used that one and the other two that go with it and it was a HUGE help. 

Even though I just joined, I've used a lot of the things you've posted on here and other forums over the years and figured things out with them. This was just the first time I needed to ask something.   

So if you thinking the theory of wire movement. Then ohm test from end to end then wiggle everything you can while watching the ohm meter. If you still holding 0 ohms then there is no issues to this circuit.

I would watch with a live data tool and see if there is common reaction.

I tried and did notice a change in the ohms, however it was inconclusive in my mind because I couldn't be sure if it was my hands moving the test lead on the contact point or the wire doing it the way I was contorted to reach everything. I'd need someone else for a 3rd or 4th hand to be sure.

A better scan tool would help as mine doesn't see everything live. 

I do know adding the ground did make the throttle % drop about 2% consistently when I would add and remove it. So I'm sure there was a ground issue, whether or not it was definitely s165 or not I cannot say. 

Remember sensor grounds are floating ground. They are not the same as body ground don't confuse them.

 

 

so is there a fix for this extremly irritating problem?

%99.99 of the time is is due to a bad alternator.  

 

have you gone through this article?

 

 

Edited February 3, 20169 yr by Me78569

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