No crank no communication Dodge Stratus

So, not a mechanic or training to be one....just some old(er) dude who's trying to help his nephew out with the listed issues...and is fascinated by the diagnostic processes involved....

No Crank, No Comm....No bus code on dashboard....2006 Dodge Stratus 2.4 Automatic

Reportedly the car ran fine, although only used once or twice a week. Then the car started and stalled just after he last time it started...has been in crank , no communication state since....about 2 weeks....Good battery, and starter....all fuses checked and relays swapped here and there with same results...I checked for a 5v reference at the throttle position sensor, no 5v reference. I need to review some more SD videos before going further with unplugging sensors.....no wiring diagram as of yet, but I'll probably get one soon.... I've checked about for any obvious breaks in wires or corrosion , none that I saw.

The battery, although tested fine, and does not have a voltage drop outside the car....Does have what I was able to get as a .349 amps? draw on battery when vehicle is in sleep mode...everything closed etc...Haven't begun to find the circuit where the draw is yet...as it involves recharging the battery...and coordinating with my nephew to assist with the process....anyhow, thank you for any assistance in advance....much appreciated.

I see that you measured a significant draw on the battery - 349mA. That's one problem, but not *the* problem. Stay focused on the no crank, no comm for now.

Speaking of, I wanted to clarify. You stated this Stratus is no crank at one point, and cranking at another. Not trying to nitpick, just wanted to be clear.

With the no comm and no 5V reference, I believe you're left with three possibilities. Shorted 5V reference, missing PCM power/ground, or failed PCM. Eliminating a shorted 5V would probably be the easiest first step, IMO. Find the violet/white wire at pin 29 of C2 at the PCM. That's the 5V feed for all the 5V reference sensors (CMP, CKP, MAP, TPS, A/C Pressure). Cut it close to the PCM, but not so close that you can't easily repair it later. Recheck for the NO BUS message and communication with the PCM. This is the fastest and easiest way to eliminate all the sensors AND wiring as suspects.

Power and ground is a little more work. You'll really need a wiring diagram for that. Mitchell DIY is an excellent option. Haynes is another. Both are very affordable compared to ProDemand or the like. Tons easier than sifting through one-make forums or Google Images to find the right diagram. :lol:

sorry to confuse....I was a little all over the place. It has not cranked since it stalled on him about 2 weeks ago. No issues prior to that incident, cranked and started consistently. I appreciate your wealth of information, amazing. I'm struggling with ECM and PCM...In the picture is this the C2 of the PCM?...where is the ECM...and lastly upon cutting the wire and putting car in crank position, what will the lack of a "no bus" message being present indicate....and if it remains...that would indicate?....I appreciate it, I just want to be clear and not assume anything...Thank you. ***couldnt figure out picture post yet....the bank in front of the underhood fuse box has four plug ins, is that the ECM or pcm...I'll research picture posting here as well....

skins247 wrote:

sorry to confuse....I was a little all over the place. It has not cranked since it stalled on him about 2 weeks ago. No issues prior to that incident, cranked and started consistently.

No worries, just wanted to make sure I understood.

I appreciate your wealth of information, amazing. I'm struggling with ECM and PCM...In the picture is this the C2 of the PCM?...where is the ECM...

Dodge calls these PCM's because it's a Powertrain module. That (generally) means that this module controls the engine AND the transmission. There is no separate engine module and transmission module. It's all one brain box.

I believe that's C2? Service info indicates that C2 is orange in color. For reference, the sequence of connector colors should be black, orange, natural (white) and green. From there, pry that stupid wire cover off, YEET it, and find the violet/white wire.

and lastly upon cutting the wire and putting car in crank position, what will the lack of a "no bus" message being present indicate....and if it remains...that would indicate?

The logic is that, if the NO BUS message is no longer present with the 5V wire snipped, then the 5V reference was causing the PCM issue. Pursue a shorted 5V reference. If the NO BUS message remains, then the 5V reference circuit had nothing to do with it. It's not an elegant test, I know. :silly:

Be sure to cycle the key off for five or ten seconds between the cutting the wire and turning the key on again. Give the PCM a moment to power down and reset. No reason to go to Crank; key on will be good enough. The engine won't start without the CKP or CMP anyway.

If NO BUS remains, then we're checking PCM powers and grounds before calling a failed PCM.

I will pursue cutting that 5v reference route...after verifying I have the correct wire. I read your response regarding my what if "no bus"...etc ...and I actually think I"m grasping it....I will purchase a diagram in the near future and get back on this project this week....and report any information learned....again your help and this entire SD site is amazing....Thanks

Haven't been able to get back over to the Stratus...having been a little scatter brained recently, I forgot to mention a few observations that may or may not help in this diagnosis....The instrument panel PRNDL indicator does not change position regardless of what position I put it in...and each letter is surrounded by the square, it is uniform on all letter although it does not appear that way in the photo...also, the reverse lights do work...Thanks again, and I'm leaning toward the Mitchell DIY diagram, is that a decent choice for this situation, or is there a better option....

With that info, I would unplug instrument cluster and see if it starts, it's just one of the modules that can cause a no start

Excellent, I'll research that connection....I'm guessing under the steering column area?

So, I needed a victory....or at least what I could see as some progress, so I chased the parasitic drain mentioned earlier....after pulling all of the common type fuses under the hood, with no change , I went to the JCase fuses....and went from .354 amp draw to .007 draw after pulling the 30a (#14 fuse) for the PCM and the ASD....I don't know if that has narrowed things for me or not (if that still means it could be any component...with the PCM controlling so much)....as mentioned , I have next to zero experience other than watching a ton of SD and researching articles....funny thing is I was doing that before my nephews car troubles began...Be safe , I will begin researching from the above info learned....and thank you again...

IMO, your draw testing puts you back on the PCM path. Have you isolated the 5V reference?

If that doesn't restore communications, we're down to PCM powers, grounds and comm lines. If you get a hold of a wiring diagram, I can help you pick out which pins need to be tested.

Also, I happened to have a Dodge in the shop last week with the same message! :silly:

I haven't snipped that wire yet...was looking at the Mitchell DIY diagram purchase for like $20...would that cover what I need for diagrams. Thanks for your help

Tyler wrote:

If you get a hold of a wiring diagram, I can help you pick out which pins need to be tested.

Thank you very much for that Tyler....greatly appreciated. I did in fact purchase the Mitchell DIY version for the vehicle...Still trying to navigate and learn where a wire splits off or if the lines on the diagram are just overlapping...any how if someone can let me know how much of a diagram , if any I can share on this forum for discussion purposes...or do I simply say C2 pin 29 vio/wht is listed as the 5v ref..and refer to wires that way,.....Just don't want to violate any terms of use on here or relating to my Mitchell purchase...My free 2 weeks are up with Scanner....and I am continuing my membership....been watching and reading quite a bit....Thank you to everyone again and be safe....

skins247 wrote:

any how if someone can let me know how much of a diagram , if any I can share on this forum for discussion purposes...or do I simply say C2 pin 29 vio/wht is listed as the 5v ref..and refer to wires that way,.....

Referring to connectors and pin numbers is the best way for others to follow along, IMO. Screenshots or snips of diagrams definitely help. Like this:



Windows Snipping Tool makes grabbing and highlighting diagrams a breeze.

support.microsoft.com/en-us/windows/use-...5f-f220-97299b865f6b

Thank you...I'm trying to avoid cutting the 5v reference, if I'm able to access the sensors without a major problem...I'm wondering if there are many more than the ones shown on this snip it....the crank shaft one is a little tricky to get to and I haven't researched the a/c sensor location yet...just wondering how many more there might be.

If I were a little closer to the Danners (I'm in Delaware).....I'd probably just have the car towed there......

skins247 wrote:

Thank you...I'm trying to avoid cutting the 5v reference, if I'm able to access the sensors without a major problem...I'm wondering if there are many more than the ones shown on this snip it....the crank shaft one is a little tricky to get to and I haven't researched the a/c sensor location yet...just wondering how many more there might be.

Not to worry, that's all of them!

You can totally go for the individual sensors, too. Nothing wrong with that at all. I only made the wire cut suggestion because it provides a clear diagnostic yes/no path AND eliminates any possibility of a shorted 5V reference wire all at the same time. If you still have no 5V reference after disconnecting all those sensors, you'll still have to disconnect C2 of the PCM and ohm the 5V reference wire to ground to verify there is no wire short.

Excellent...and I totally get your suggestion/reasoning for cutting the ref wire...still may have to be done...just looked at that tightly wrapped harness...room...my lack of experience in cutting and mending properly...etc etc...again many thanks folks

Just build up the courage cut the wire and be done with it. Solder it back together when your done. It’s faster