Truck shifting problems and shutting down randomly

[DevanA]

Hi everyone, I recently bought a 2005 Dodge 2500 with the CTD engine and I'm having some issues with the power train that seem to be electrical. The first issue is that the engine will just shut off randomly. The gauge cluster also goes dead except for the idiot lights and there is a ticking that sounds like it is coming from under the fuse box in the engine bay. This has happened 3 times now and with the exception of the first time, the truck won't start back up (the starter still cranks) until the clicking stops. The other problem is that the truck is "shuttle shifting" between first and second gear under very light acceleration (less than an 1/8th of WOT.) It also will not shift out of first gear unless you baby it, otherwise it will go all the way to redline and refuse to shift. When it does shift it goes into gear pretty abruptly. I just changed the governor pressure sensor (OEM) and solenoid (updated Borg Warner) thinking that would solve the problem but it seems to have made no improvement in the shifting. The codes that pop up are p0234 (turbocharger over boost) and p2509 (ECM/PCM power input signal intermittent). At this point Im not really sure where to look next and definitely don't want to keep throwing parts at it. Any ideas on what could be causing these problems? Thanks

 

[cerberusiam]

The 2509 is power lost to the ECU. Might be from disconnecting batteries but you need to clear it and see if it comes back. If it keeps coming back start looking at battery cables, connections, and grounds. With the truck shtting down like that either there is a problem with the power supply or you possibly have a peripheral causing high, the fan is good candidate for that as is the data port under the steering column in the cab. If the gauage cluster goes dead the bus is dead and that means a bad connection or the ECU went into reset mode.

Tjhe shuttle shift under very light htrottle is pretty typical until the problem with the gov pressure rise is fixed. A shift enhancer will help a lot, sometimes adjusting the font band will help. You still have issues somewhere if it won't upshift under hard throttle. Either the transdcuer oyu put in is bad or ther eis a problem with the VB harness. Either one could be the source of the problem. If you put a gauage on the gov pressur eport and check I will bet the gov pressure is just not coming up like it should.

 

[sag2]

The P2509 is saying the B+ went away while the ignition (switched battery) was on. There are three B+ wires feeding the ECM from the PDC. Check for the connections and clean and tighten them. Don't forget the B+ stud next to the battery that feeds the PDC.

 

[DevanA]

Sorry for this late response but I haven't had Internet over the weekend. Ill look take a closer look at the connections to the ECM this week, thank you both for the suggestions. Another thing to add about the shifting problem though is that i forgot to unhook the battery cables and reset the computer after changing the gov. pressure sensor/ solenoid, could this also be part of the problem? If not, where/how do i test the solenoid's pressure and what should the range be?

 

[cerberusiam]

No, there is no reset on the gov solenoid required. It simply responds to what the ECU tells it based on inputs.

The output of the operation of the transducer as pressure can be viewed by putting a gauge on the governor pressure port on the transmission. On jack stands, you can run the shift points and rpms to see if the pressure curve is even and matches wheel speed, or, there are hangs, jumps, or it just doesn't rise. Up to about 15 mph the gov presure should mirror wheel speed. From that point up the pressure should starting rising 2x wheel speed. By 40 mph it should be reading 80 psi and all the shifts should have occured. The exact pressures are sometimes not important and can vary based on build, as long as the curve rises evenly as speed increase that is what you are looking for.

What you will likely see is gov pressure at 5 mph or less, sometimes 10 mph or less at zero with very light throttle. This is what causes the shuttle shift, no pressure stopped and low pressure at low throttle opening.

 

[DevanA]

Ok I'll have to check it out when I get a chance. Thank you

 

[Prairie Dog]

The ECM and several others items are grounded through these bolts in the edge of the qtr. panel. Remove each one, clean any corrosion off the threads and reinstall. These grounds can cause all kinds of problems including losing ECM power.

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[cerberusiam]

Also, check all the battery cable ends CAREFULLY. If there is any question of integrity replace them. Bad contact in the clamp and corrosion in the cable itself will raise total havoc with mpg, injectors operation, trans shifting, and every other thing imaginable. My son just got done redoing all the cable connections to the battery on his 05 and there were many issues inside the cable sheath and the clamp itself. The cables are sealed well enough to prevent corrosion starting in them and even though volts and resistance chekc out it screws up the ECU. Slow starting, noisey injectors, floating contrbution rates, intermittent shift problems have now all disappeared. None of this was obvious until the cable ends were cut off and examined.

 

[DevanA]

Thanks for all the help so far guys. I havent looked over the main battery cables very well yet but while I was taking a look at the rest of the wiring I noticed this one was cut. Any ideas on why or what it goes to?

 

[cerberusiam]

That looks like the main power bus to the ECU. On my truck it runs over and zip tied to the positve battery cable then runs into the harness at the ECU.

Do you have a wire with a connector that has no end? It switches from red to blue in what looks like a fusible link. Maybe it was powered from somewhere else?

 

[DevanA]

Ok so I finally got some time to take a good look at the wiring on the truck and found a few things. The first was a small split on the drivers side B+ cable

I also noticed some corrosion on the 3 power wires on the ECM (not quite sure how to go about fixing/cleaning them up)

I also realized that the previous owner didnt do a very good job wiring up the fog lamps they installed on the truck. They grounded the lights on the same quarter panel bolt as the ECM is grounded to and put the light ground closer to the fender than the ECM ground. They also put the power wire straight to an open bank on the fuse box with no switch to turn the lights off or anything, and upon further following of their wiring job I found this mess and a fuseable link that looks burnt up. Im really not sure what to make of the red wire that runs along with the other wires in the plow control wiring harness.

I also found a sensor on the transmission (near gear selector cable) that had a fair amount of transmission fluid in the plug. Is this the TTVA? If not, what is it? Could the fluid in this plug cause a short in the ECM and give me the problems I'm having?

While i was down there I also saw that there is a broken ground cable attached to the body. Anyone know what it goes to? There doesn't seem to be anything really close to it that it would connect to.

The last thing I noticed was a plug going into the cylinder head had motor oil in it, is this normal?

 

[DevanA]

Plug going to cylinder head

 

[DevanA]

I forgot to mention that the ECM is getting its power from the black wire with the yellow connector in the first 2 photos I posted on this thread. Is this spot ok, or should i move it somewhere else?

 

[cerberusiam]

I forgot to mention that the ECM is getting its power from the black wire with the yellow connector in the first 2 photos I posted on this thread. Is this spot ok, or should i move it somewhere else?

The cut red wire right below thta black one is where the ECM power was originaly sources. I don't think there is any difference in gabbing power above or below that juncture though I have torn that piece all apart. I would efinitely used soldered connections rather then crimp on that wire.and make darn sure everyhting is clean and grease don the mounting post. That is likely the source of your random 2509.

The box on the transmission with oil in it is the trans range sensor (gears, backup lights, neutral safety switch). Won't cause the truck to shut down but it will mess with shifting. They leak it is replacement time. FYI, the TTVA motor is the component directly above and in front of the range sensor.


The plug on the head is the inejctor harness, you have 3 of them. The connector goes directly into the valve cover so it is hot diesel oil behind it. They are plastic and sealed until they leak. Clean the male and femal portion up real well with electical contact cleaner and blow dry. You could add osme dielectric grase on reassembly then periodically check to see if the oil comes back. If it does the connector needs repalced in the VC spacer. Might as well do all 3 when you do it.