Dodge Repair Questions? Ask a Mechanic for Answers ASAP
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It's kind of a tough call at this point. I'd like for you to check right at the starter solenoid for a good crank signal out of the starter relay when it's not cooperating. The relay output has to travel through the Power Distribution Center and out at least one connector to get there and things can happen along the way. The relay itself can be a problem, although it's a pretty rare occurrence. Exchanging the starter relay for another one from a non-critical location might tell you something. Jumpering the circuit right at the relay connectors is also an option. Pins 30 and 87 of the relay (printed under the relay body) will send power straight to the starter solenoid when jumpered together. If it still doesn't get power to the starter, we'd need to take a closer look at the wiring or the PDC itself.
It wouldn't hurt to check for codes stored in your engine controller (PCM). Turn the key off/ on three times and watch the odometer. Any codes stored will be displayed, with "P-done" or simply "done" displayed at the end of the test. If something comes up, write me back.
Ooof. The whole problem may be with the PCM not being awake or a Sentry Key situation. Or either system is OK, but the communication bus is down.
I didn't see anything in your first post that indicated the van would die while driving, it was just a no-crank no-start problem. Let me know if it's something other than that.
Let's check the vehicle communication bus for voltage. Go to the data link connector and find the #2 pin. This would be the top row, second pin from the left if the connector is oriented so that the wider portion is on top. Check it with the key on and your meter set on 20 volts.
A normal PCI bus voltage is somewhere between 1 and 2 volts, made up of multitudes of voltage spikes. The bus is flat dead at rest, so voltage is put ON it to produce a communcation signal, unlike the old CCD bus.
If it's OK right now and working take note of the voltage during a good time like that and compare it to when it's not feeling so well.
The relay click you first described reminded me of something like this, where the starter relay is very briefly energized, then the ground (neutral safety) path is removed. It sounds like a light <tick> rather than the whole click.
Check underhood for signs of battery acid leakage. If it gets bad enough it will seep into a section of harness that runs directly below the battery tray and contaminate the individual circuit insulation of each wire. Voltage from unrelated circuits can bleed across that way and if it gets into the PCI bus... it can get ugly. If you see much more voltage than expected, this might be the first place to look. It requires removal of the tray.
I have to send this as an answer, but don't consider accepting it until we've made some real progress.
Good luck and keep me posted!
Well, it's good to have it back at home anyway lol! What you saw on the bus voltage test and the 1-2-3 key test for codes now is what I'd expect on a working van. It's pretty clear that the bus was down (up?) for whatever reason before, so there's a pretty good chance that engine start was interrupted by the anti-theft system.
Let's try something for the next time that it acts up. Even if the bus goes down, the PCM should still be intact and unaffected by the event other than not allowing the engine to start. Having no codes stored after something like this makes me wonder if the PCM itself may be to blame.
By setting a code of your choosing, we will know better next time after it wakes up whether the PCM is losing memory during the down times. I tend to use the throttle position sensor as my code-of-choice, but pretty much anything will do. Just disconnect the TPS with the key on or running and when you see a MIL illumination with the engine running, we've set the trap. Scan it to see the exact code and then check it again the next time it wakes back up.
A battery disconnect will clear codes, so make sure it doesn't lose battery power between now and then.
Being a newer owner, you won't know what's been done to the van in its past. Look for stuff like aftermarket radio, theft system, remote start, entertainment systems... stuff that requires cutting into the harnesses or running screws into the vehicle at various points. If you find the bus wire to go low (shorted to ground), we might be looking at a harness rub or dangling wire short. A higher voltage might be a voltage bleed from another circuit or an intermittently-bad module on the bus. These things can take some time to sort out, but if you're good with that... so am I.
Talk later, Ed
I'm surprised too! It's my understanding that the MIL might go out after so many successful starts (good trips) but the code should remain for quite some time. But if you haven't even had a no-start event since the P0123 was set... I'm not sure what to say.
Plan B would be to set the same code if you wind up with a no-crank condition again. Do the same thing, then check to see if the code actually set while the engine couldn't be started. That would tell us (somewhat) whether the PCM was active during the down time.
Another thing you can do to get an idea whether the PCM is awake is to listen for a one-second run of the fuel pump at key-on. No cranking required. It should fire the pump if it's awake but it won't keep it energized until it sees the engine turning (cam/ crank signal). No pump operation takes us in the direction of the PCM or its powers/ grounds/ wiring.
OK, I got ya. Check it out to see one way or the other.
Thanks Bud. Good info is always appreciated! I don't use workarounds like this in real life, so it's an ongoing process and your feedback is very useful.. Our scan tools have the depth to tell us if the PCM has recently lost memory, etc., so I'm kinda making up some of this stuff as I go.
It's worth checking, but it doesn't explain why the PCM was a no-respnse at one point. Even in SKIM lockdown, I believe there should be communication possible with the PCM. But it's sure worth checking out because I can't account for every possibility...
Good thought, Bud. I guess all those years of wrenching weren't for nothing, huh?
'Mornin, Bud! That church parking lot seems to be one of its favorites, doesn't it lol?
Losing the TPS code makes it look bad for the PCM. I'm not completely sure as I sit here this morning (day off) whether a short to the 5v power feeds on your major sensors will take this controller completely down. The NGC unit uses two 5v generators and I think it was designed for this purpose... to keep the engine running in the case of an intermittent short. It's one of those things I need to bone up on because it really happens so seldom on the newer vehicles.
Did you trade keys with Chelsea before this happened? It just occurred to me that you may have a separate theft system from the SKIM (grey key) functions. If you use the power lock switch to lock the van as exiting, it sets the alarm. If the unlock switch in the door fails as you manually unlock the van later, the theft system will be activated. Having no lights and horn, that theory seems pretty weak, but I thought I'd include it anyway.
Since there's a possibility that moisture might play a part, create some of your own. Give the underhood a soaking and see if it will act up for you. A hot engine will create some extra steam, which might be good. Close the hood and let it steam-soak for a bit and see what happens.
One last question for now... how many miles does the van have on it?
Thanks Bud. It was a shot in the dark, but I had to ask. If the door alarm (VTSS) was really at fault, there would be all kinds of noise and lights flashing... which you don't have.
I'm leaning pretty heavily toward the PCM at this point as being your problem. It doesn't fit perfectly because I'd expect it to die while driving at least occasionally. But all you have is a no-crank no-start every once in a while. WITH NO CODES.
The loss of the TPS code is one of the major reasons I'm going this way right now. It would be nice to know if the fuel pump humms for a second at key-on and what the PCI voltage is while the van is disabled/ down. But loss of communication alone should cheese off the PCM enough to have it set codes of its own, including SKIM transponder key codes. The PCM almost has to be asleep during these times.
The good news is that it should be covered free of charge under the extended 8 years, 80,000 mile Federal emission warranty. The trick will be convincing your local Dodge dealer to replace it for you based on what we've seen here. They may insist on seeing the van act up and getting a positive diagnosis before releasing a (rather expensive) PCM and we both know the trick is getting the van to act up!
New thought. There was a recall a few years ago for PCM connectors having problems with water intrusion. The weatherpack was getting bunched up during installation on the PCM and might provide the avenue for water entry. In the right place, water could short across circuits and possibly take the bus down or something similar. I don't remember the exact year for the recall, but it's right around the same as your van.
The PCM lives in a rather inhospitable place, just below and to the rear of the left headlamp. If you lie on the ground and slide under the front skirt of the van you will see it tucked up just behind the left wheel well splash shield. I don't know how much you can tell from there, but the recall involved looking at the connectors (4 in all) to see if weatherpack was bunched up in the release tab area. This is the top of the connector, the side you can't see without a mirror.
If you decide to pull the connectors off for inspection, there is a red slide-lock that must be pulled outward from the PCM direction. Then the black thumb release tab will click when pressed and the connector will come off. Be prepared for plenty of road crud in the eyes (lol)!
The recall had us replacing the connector(s) as required if the weather pack was damaged or if there was green groties-type of corrosion within the socket. In the case of groties, it got a new controller.
Regardless (at this point) of whether the recall applied to your van or not, check it out for weather-tightness. A garden hose shot might be the trick... it's off the normal underhood area, so hosing this spot won't affect anything else. It gets a fair amount of road spray while driving, too.
If the bus got shorted to voltage while driving, the SKIM system wouldn't be activated until the next key cycle, either. The engine won't die while driving once SKIM has given the OK to start on the last key cycle. If the loss of bus communication isn't noticed, the next attempt to start will be when the no-start will show up.
Finally... maybe something that makes some sense. It's not perfect either, Bud, but maybe you can help me out here!
OK. Good luck!
Good work Bud! There are repair packages for the NGC connectors. While it will likely come with far more stuff than you actually need, but it will certainly have enough.
All the connectors on the NGC unit are interchangable.. can be plugged in at any location. The way that they prevent this is to color code the connector and the PCM. If you can tell what color the connector is, it would be best to replace it with one that's the same... just so nobody has trouble down the road. The colors are black (C1), orange, white and green (C4). I don't recall the order for the center two and it may be an issue when you go to buy/ order one, so count from the black connector to the green (C1 thru C4). I'm pretty sure the far-front connector is the black/ C1 unit.
All the existing wires and terminals in the harness can be transferred, but it's quite likely one or more terminals may need to be replaced. The kit comes with enough pigtails to replace EVERY terminal in the connector... and then some!
But I have to warn you.. sometimes it's the connector, sometimes it's the module. The NGC connector inserts pretty solidly into the PCM mount, making it difficult to wiggle the connector only. It's going to move the electrical board within the controller box, so that may actually be the problem. If you can't find a thing wrong with the terminals or wiring, it may very well be that you need a PCM (a covered component).
Take another look to be sure that there are no terminals pushed out from near-flush on the controller side and no water/ corrosion present inside the connector mold. Pull on the individual wires to see if a conductor might be broken within the wire insulation. Something like this could be nothing worse than a loss of power or ground to the controller.
A quick look at the PCM terminals a socket would be good, just to see if there's any sign of obvious discoloration/ corrosion/ damage/ moisture. Your PCM may have taken a hit at some time to start this, but it shouldn't matter for warranty purposes. You have no knowledge of an accident or what caused it to have these two damaged connector molds. There's no way to tell for sure if the damage or stalling are even related.
But since you've gotten the engine not only to be in a no-start state, but gotten it to stall, I'd have to say you're 99% of the way to the finish! The stalling, something that hadn't happened before, is the best news I could hope for right now!
Bud, it fits! Gawd I love it when things make sense. That's a B+ wire! Road salt does damage of this sort over time from a small wound like that... eats the wire from the inside out.
The corrosion will stop once you get it sealed, but it probably extends at least an inch in either direction... maybe more. Solder doesn't stick well to "green" wire, so you might have to cut it back a fair distance either way. If there isn't enough wire left at the connector, a pigtail might be the best way to go. You would have to buy that whole kit to get a single pigtail or I could send you one in the mail if you can wait that long. Add in some self-sealing shrink tube and it'll be as good as new!
If that's OK with you, send me a mailing address through the Private Messaging system here at JA unless you're comfortable with having your name and address visible to anyone with access to the site.
To get there, click on dodgerench at the bottom left of this post. It takes you to my profile, where there will be a PM tab that you can click. It's just email from that point. I promise you it will be no trouble and I'll include a brief step-by-step for terminal removal.
Great work Bud! I do love a happy ending :o)
Very kind words, Bud! Don't forget that you're the one that found the problem and will be fixing it LOL! I'm all good with what you posted with your question for payment. Feedback is bonus!
Hearing that you're back on the road and happy is really the best part. If I never had the opportunity to work with great folks like yourself I'd just stick to my day job. The expererience that we had here with a rather unusual problem will help me do better in the future, so I'm thankful as well.
Take care, Bud! Write back any time.