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Discussion Starter · #1 ·
Hello everyone:
Path that i went threw from sigma wagon F07W 6g72 sohc not starting.

What happened is that one cold morning -10 degrees, it started and drove like 3 meters and engine stopped and is not starting.

When started digging online i went threw this : Testing The Power Transistor, Ignition Coil, And Crank Sensor

Did all the tests and what failed is that Power Transistor Switching Signal Output is not going out as The Power Transistor Is NOT Getting An Activation Signal from ECU

did not did all from here as i found it later on NO SPARK troubleshooting guide

so i left nothing changed under hood

took of ECU and found that it has been burned:
293952

So after all the find i got those capacitors re welded and that burned part changed
293953


and car still don't make any spark

while tested all the cam and crank sensors they give the signal but the ECU is not providing ignition signal

maybe anyone have or know where to get scheme of this ECU board ? to track all the paths ?

or I'm missing something ?

car is Diamante Wagon engine is same as in all mitc chrysler's etc. 6g72sohc 12v

i have did small wiki of my own: 6g72 sohc don't start
 

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93 NA ATX 3000gt DOHC
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I have no way to date that ECU number and don’t know the age of your car since you didn’t include the model year in post.

But the capacitors in that board look to be same age found in early 90’s 3S cars. The C105 capacitor looks as though it leaked and could be the burnt looking area or the electrolyte that leaked shorted one of the near by flat components on the board causing the burnt look.

In either case all 4 capacitors need to be replaced and board cleaned with alcohol where the burnt look appears, to remove the leaked electrolyte and look for brunt components or traces in that area.
 

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Discussion Starter · #3 ·
yes did not mentioned year but model is end of post "car is Diamante Wagon engine is same as in all mitc chrysler's etc. 6g72sohc 12v "
in my papers it states 1993 first registration maybe chassis number will help 6MMYRP45PT000303
it's nice that its 303rd made :D and to japan catalogs its F07W chassis code

i have noticed that board number is looking similar to 3k ECU's just board number is with extra letter in end

is it possible to find schemes of them ?

will do the chemical cleaning to see maybe something is under burnt part
 

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I saw the model just couldn’t find the year which was important. Being a ’93 it is what I guessed looking at the board and could tell it was not a turbo because they only have 3 barrel capacitors, while the NA (naturally aspirated) have 4 barrel capacitors. And yes it looks just like the ECU in my ’93 3K, but the 3K’s and Stealth’s ECU part numbers start with a MD while yours starts with a AW and the following numbers 333975 don’t match anything I can find listed in the attached ECU list. I’ve never seen any schematics available for the boards themselves.


But your board needs all 4 capacitors replaced, not just the cleaning to remove electrolyte and visually look for other problems. My engine quit ~ 8 years ago when ECU was ~ 20 years old and only thing I did was replace the 4 barrel electrolytic capacitors and it fired up and is still running. I couldn’t see the micro-farad ratings in your pictures, but since your board looks just like mine I’m guessing you have (2) 47 micro-farad 50 volt, (1) 100 micro-farad 16 volt, (1) 22 micro-farad 50 volt.
 

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Discussion Starter · #5 ·
problem is that all capacitors are replaced but car still don't start, that burned ground thing was replaced with air one

my tests leaded me to no ignition signal from ecu
i mean signal from ecu that goes to PW transistor then to coil ->distributor-> spark
cam and crank sensors works fine

can it be case for sure if the micro-farad is same as was but i think one that has to be 50volt is bit higher as radio store did not had same ones ?
 

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Discussion Starter · #8 ·
according to this i think i can use
MD192592
E2T35692
ECU for my wagon
 

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Discussion Starter · #9 ·
went threw many formation

and seems that i need to recheck correct pin where ECU is not generating ignition signal
 

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problem is that all capacitors are replaced but car still don't start, that burned ground thing was replaced with air one

.................

can it be case for sure if the micro-farad is same as was but i think one that has to be 50volt is bit higher as radio store did not had same ones ?
Did you replace the capacitors or the radio shop? Questioning because the are polarity sensitive, meaning one lead is positive and one negative, reversed capacitors won’t work and sometimes even explode which a radio repair shop should already know. Higher voltage on a capacitor is OK because it just indicates what a capacitor is able to handle, but the micro-farad must be the same as original designed for a circuit.

my tests leaded me to no ignition signal from ecu
i mean signal from ecu that goes to PW transistor then to coil ->distributor-> spark
cam and crank sensors works fine
I’m not sure how you tested the ECU output to PTU and determined it was a problem, because that ECU output is hard to test without an oscilloscope, myself and a more experienced member here helped another member with same problem on a SOHC engine awhile back and IIRC could never determine for sure if that output was correct or not, when I get time I’ll try to find that thread and link it if your interested in reading it.

i see my board is same as : Car won't start???? but ca't find right part number of it, as i might need to use that 1991 dodge stealth rt n/a ECU
All the NA engine ECU boards look the same, the part# for that board can be found in ECU ID link I attached earlier part# is MD159963. BUT it’s the wrong ECU for your car as it is for a DOHC ’91-’92 engine. If you’re looking for part# for a SOHC ’93 engine in a Stealth or 3S that part# is MD188207 if manual transmission or MD188206 if automatic transmission.

found this and thinking that it might be problem that i have
Might be case if yours is an automatic, because the MD188206 is included in that list.

according to this i think i can use
MD192592
E2T35692
ECU for my wagon
That’s for a ’94 SOHC and yours is a ’93, so it might work but there may be some unusual problems show up. If yours is an automatic (don’t recall you indicating), as I said above the MD188206 is what was in SOHC ’93 automatics for Stealth’s and 3K’s.

and seems that i need to recheck correct pin where ECU is not generating ignition signal
All that info on ECU pinout’s can only be use if you can find pinout for your present ECU to be able to compare. Pinout’s in Stealth’s and 3K’s often vary slightly between model years and trim levels.
 

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Discussion Starter · #11 ·
i checked the wire with tester from engine by to ecu pin
and there where no flashing
while both cam and crank
was flashing fine

will get ecu from sedan car with SOHC automatic engine to see if it will run, if will means that i will need to find specialist o fix this ecu to have it as spare

that thread would be nice to read
 
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