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Damn....I'm looking at the 2.0/2.4Turbo pin-outs from the PCM and the only refernces to anything auto-tranny related are on C4 (GREEN). I don't know if the 2.0/2.4T PCM/ECU is the same in the SRT-4 as the PT/GT Cruiser. But here is the image file anyway. I'm not posting it inline to the post becuase it is big and would be distracting if it's not relevant.
I'm thinking pin 27? Of course, I'm also car-stupid. :lol:
 

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Yes, but it will help out the Cali crowd also...this interests me. A true ECU/PCM hack!
And I loves hacking the crap out of things.
I figure we find out EXACTLY what pinout on the PCM is throwing these codes, figure out what the correct voltage it's looking for, then spike that with a resistor load to "fool" it for inspection. I wouldn't want to run it all the time, but a good "before-you-go-get-inspected" mod would be nice.
I'm still thinking it lies in the C4 connector somewhere. Of course, in the old days there was a separate TCU (Transmission Control Unit) and ECU (Engine Control Unit) but now there it's like Highlander...there can only be ONE! And it's the PCM (Powertrain Control Module). Or am I all bass-ackwards?
 

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cali said:
Ya know, its lazyness that those codes are even still in the sw.
Damn right, sheer laziness. They figured since the kits aren't for street use (legally) no need to zero-out the programming for it.
 

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I guess it's for the 40TE Auto-tranny?
"The solenoid assembly also contains pressure
switches that monitor and send hydraulic circuit
information to the PCM/TCM. Likewise, the pressure
switches can only be service by replacing the assembly.
PRESSURE SWITCHES
The PCM/TCM relies on three pressure switches to
monitor fluid pressure in the L/R, 2/4, and OD hydraulic circuits. The primary purpose of these switches is to help the PCM/TCM detect when clutch circuit hydraulic failures occur. The range for the pressure switch closing and opening points is 11-23
psi. Typically the switch opening point will be approximately one psi lower than the closing point. For example, a switch may close at 18 psi and open at 17 psi.
A Diagnostic Trouble Code (DTC) will set if the
PCM/TCM senses any switch open or closed at the
wrong time in a given gear.
The PCM/TCM also tests the 2/4 and OD pressure
switches when they are normally off (OD and 2/4 are
tested in 1st gear, OD in 2nd gear, and 2/4 in 3rd
gear). The test simply verifies that they are operational,
by looking for a closed state when the corresponding
element is applied. Immediately after a
shift into 1st, 2nd, or 3rd gear with the engine speed
above 1000 rpm, the PCM/TCM momentarily turns
on element pressure to the 2/4 and/or OD clutch circuits
to identify that the appropriate switch has
closed. If it doesn’t close, it is tested again. If the
switch fails to close the second time, the appropriate
Diagnostic Trouble Code (DTC) will set."
 

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Transmission Control System Wiring

Well, I dug this out...maybe it will help you.
Yeah, I'm thinking some sort of "piggy-back", only coming off the green C4 connector on the S3R PCM. Basically, if someone builds an integrated circuit in a nice weatherproof box that sends all the correct signals back to the PCM, it will fool it. But I'm car stupid...but good at research anyway. :lol:
 

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Yes, but if someone can build "the magic S3R box" then all they would have to do is splice it into the C4 green connector and be done with it. A lot easier to splice into the connectors than to take the car back to stock. But you would need a S3R to test/try it all out on.
But since this "box" doesn't exist, Dale's way may be the only way.
 

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phrozen said:
Ok guys. I will put my open-source piggy-back development on hold to fix this problem first, especially since I am getting Stage 3 very soon.

I think I can design a circuit to make this work. Can we get the PT cruiser schematics posted?

Maybe they are already.. I noticed a few attachments in here, but I didn't take the time to download all of them.

We'll need the full PT cruiser schemactics (if that's where this ECU came from) and I already have the SRT-4 schematics.

I like the description of how it works. I'll think about it when I get home tonight and see what I can do.

Unfortunately, I don't have my stage 3 kit yet. So even if I do come up with a circuit, I won't have any way of testing it for at least another month.

But, to the original poster... See if you can hold out a few more days. I'll let you know what I estimate this will take to do.

I don't want to have to go back to Stage 0 for my car. Sounds like a pain in the ass.
The attachments I posted were from the PL-body Neon/SRT manuals. Isn't the PT Cruiser based on the same chassis/wiring as the Neon or am I just a big fat moron?
Anyway, what's really important is the tranny stuff. Somewhere in there are the wires going to the TCU/TCM that controls the auto-tranny. Searching on the net will find you an auto-tranny for a 2002 PT Cruiser for $1100, model 604. And searching on the net for the Neon auto tranny reveals:
A604
Also known as
40TE; 41TE; 41AE

Used in Chrysler non LH cars (with transverse engines)

Versions of this transmission were used from 1989-up. In 1995 Chrysler added an additional mount over the differential. This required a case change to add a pad that had three vertical bolt holes and one horizontal bolt hole to hold the mount. In mid 1996 Chrysler eliminated the separate PRNDL and neutral safety switches that screwed into the case and combined their function into one switch that is now internally mounted on the valve body. This required an additional case change. There were MANY variations over the years and MANY parts do NOT interchange from year to year or model to model. Do not confuse with the non-overdrive A404/A413/A470/A670 series of transmissions.

So I think the answer is still in the attachments I posted.
Quick! Prove me wrong before my head swells! :rofl:
 

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And aren't the ECUs for the PT/GT Cruisers the same as the ones for the Neon/SRT, just the programming may be different? Pinouts should have stayed the same though, to save on wiring costs and troubleshooting time/costs during drivetrain testing at the factory.
 

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never2muchboost said:
me and phrozen are working on it now,

so far we have the trans relay codes taken care of:thumbsup: and looks like only one or two other issues with the solenoid circuits that need to be ironed out.just got back from radioshack with some goodies and working on those now!
so far were very optimistic

stay tuned.....................................
Outstanding! Be sure to post a Radio Shack parts list and wiring/circuit diagrams. I'm sure a lot of people would be grateful if they didn't have to remove S3R to get the car to pass inspection.
The tranny codes just needed current passed to the correct pins on C4, right?
 

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P0750 Shift Solenoid A Malfunction

Sounds like while YES the PCM thinks it has a tranny now due to you providing current to the right pins, it's now not seeing the proper signals from it on another pin somewhere and thinks there's a problem with the sensors on the tranny itself.

Damn, fix one thing and get a completely new error code. Look at C4 and everything "TRS" on it. TRS stands for "Transmission Relay Solenoid"? I don't know, not familiar with the Neon auto-tranny. I bet it's looking for signals along those pins, which is why it's saying Solenoid A malfunction because it's not seeing input from Solenoid A so it's throwing the code because it thinks it's broke.
 

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Out-frickin'-STANDING! Good work guys! Now....TTIWWP! :lol:
How did you guys get the C4 connector to use? No way to plice it in-line with those S3R owners that have toys or is this to replace the toys connector during "inspection" only? If so, the inspection people won't do anything about a hanging-loose C4 connector from toys just dangling in the engine bay? How big's the box? Can it be hidden in the fenderwell or something easily?
Questions questions questions today!
 

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You two are SERIOUS car nerds! :lol:
Good show! I'm surprised a vendor hasn't contacted you yet to "assist" with getting these into production and sold through a vendor site. <ahem>
 
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