QuestionQUESTION: I was trying to trace the coolant sensor signal from the pcm to the sensor, bought the hanes and chilton and factory manuals to see the wiring diagram for the pcm and the sensor.
Well it says that it comes from pin 2 of the pcm. The pcm does not have a pin 2 (pcm part # p 04797708) also the chilton manual gives another pcm diagram but it too does not have the pin which is supposed to be carrying the coolant sensor signal. VIN 2C3HD56F5SH603481, CAR MADE IN CANADA DEC OF 1994 BUT IS SUPPOSED TO BE A 1995. IT IS AN LHS AS FAR AS I CAN MAKE OUT. I also need a pin out for the data output terminal it is a blue plug under the dash. This whole car is a mess an orphen, not even the factory shop manual has the wiring for this car so if you have a piece of information that would tell me the pin out of the pcm and the 60 way plug. It would help me also if I could get a manual for this car. I think this one has some mercedes benz things in it, since even the chrysler co. has orphaned it and I sent the manual back. I have to repair the car it has been a disaster from day one. The PCM is fine I have an open ckt to the coolant sensor that brings the sensor signal to the sensor. I tried another pcm and it has the same symptoms and error codes could it be that this model is the same as another year? It should have been a simple fix a five vole signal from the pcm to the sensor which varies with the sensors resistance. But the wiring goes all over the place and is against the engine block at the back and gets roasted by the engine. Very poor design and wires are too thin. Well no one at chrysler had any idea of which manual would handle thi model. Hope you have an idea.
ANSWER: Hi James,
I have the '94 shop manual which I believe is applicable to your '95 model. I believe the vehicle is either a Chrysler LHS or New Yorker, not a Concorde, for what it matters based upon the D in the 5th place of the VIN.
I believe that you have mistaken the transmission control module which is mounted on the left inner fender for the powertrain controller, as it indeed has no wire on pin 2 of its plug.
The powertrain controller is hidden from view by the air cleaner housing in the right front corner of the engine compartment, and is accessed by first removing the air cleaner cover and filter, remove clamps that hold the air intake duct to the housing (this is on the fender side of the unit, I believe), remove the bolts that hold the housing to the engine compartment. Then lift it out and detach the inlet duct, and remove it entirely.
Then you will see the powertrain controller which is held by a stud bolt and a push pin. Remove/release the stud bolt, and you push down on the collar of the push pin device with a screwdriver and use a pliers to pull up on the center pin of the push pin. Then you can lift up the controller and find the 60-way connector. You will find that it does have a tan/black wire on pin 2 that comes from the coolant temp sensor. Its path takes it to one of 5 connectors/disconnects at the right rear near the firewall and attched to the right strut tower. The lower plug next to the strut tower has 14 pins and the tan/black is at pin 7 of that disconnect. From the disconnect it goes along the engine to the sensor. The black/light blue ground wire goes to pin 4 at the pcm, through a couple of splices and then through pin 3 of the same disconnect plug I described above. That wire is used by many sensors as a reference ground. You are correct that pin 2 should show a 5 volt reference value, and the pcm presumably senses the temp via measuring the current flow from pin 2 through the sensor to pin 4, both at the pcm 60-way. The wires from the sensor to the firewall appears to flow in a harness with those for the knock sensor/camshaft position sensor, between the spark plug caps and the injector connectors on the right side of the engine.
I hope this proves helpful to you.
Roland
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QUESTION: the PCM has the 5volt sensor signal on pin 2 and I jumpered to the sensor the code of 22 went away, and the temp gauge works. so that is fine. the 14 pin plug though is not jumping out at me since there are 4 large plugs on the strut housing. and if it is the largest which white and is at the left bottom of the 4 plug set. Pin 7 or what I think is pin 7 has 13.5 volts on it and for sure is not the correct pin for me to consider on that plug. So there is no pin markings I could see in order to make my count to pin 7 assuming I have the right plug. I used a very sharp set of small needles to pierce the insulation and it works great for testing between wire runs. But it would take a long time to determined which wire is which. Also the car is very old and the wire colors have faded making it difficult to tell which color is correct. Is it blue and black or black and blue etc.. is it tan or white or yellow? So looking at the plugs on the array of 4 plugs, which is the right one? and where do I start counting from? That is pin 1 to which ever pin I need to find. I was not able to remove any plug out of their socket even though I lifted up on the locking tab, I did not want to tear out the wires trying. A suggestion on this would help as well. The check engine light stays on but a scanner tool will remove that one, once the coolant connection is solved. My final error code which just showed up 2222 not sure but may be something to do with the ABS system. Honestly this car is a real lemon, I bought it from my father even though I had misgivings and I should not have bought it. Problems: complete cooling system changed, transmission changed, transmission control module changed. both cv joints changed complete. steering assembly changed, it keeps having problems My other older cars just have normal wear and tear problems but my Chrysler products of which I have two keep falling apart. my other one is a 1995 Plymouth neon and it just stops running for no reason then starts up again after a few days with no symptoms what so ever, mechanics have no idea since when it is working normally there are no error codes every thing works but no spark, worst kind of problem it is intermittent and can't be trusted to drive. can go for weeks and then quits. I had one clue if you go over a dirt road washboard like, it seems to make it act up I think I will take a rubber hammer and whale the tar out of the PCM and connections that may make it act up.
AnswerHi James,
As best I can tell from the drawings, there should be 5 black colored muli-wire disconnects at the strut tower, three for the engine, two for the transmission wiring. The engine's are 16,14,and 2-pin, while the trans's are 12 and 8-pin. The sensor tan/black wire would be on the 14-pin disconnect, and pin 7 would be an outside pin of the second row of 4 pins, counting fron the locking tab's nearest row of pins being 1-3. I can't be sure if it would be left or the right-most pin of the second four. The black/light blue is in fact in that top row of three as it is #3, and number 7 would be directly below #3, offset slightly to the outside. But left or right-most I can't be sure.
On the Neon, if the recovery occurs after cooling down, within an hour, then I would believe that either the cam or crank sensor is in an early stage of failure but not setting a fault code.
On the 2222, I haven't seen codes like that so early in the obd-II regime. Any counts by flashing of the check engine light? The manuals for the ABS seem to say that the codes are spelled out in text messages, not numbers, as seen on the Chrysler DRB-III.
I hope the descriptions above help you to find where the tan/black is broken open.
Roland
