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Discussion Starter #1
i have a 2000 e430 4matic ive been dealing with trans issue after replacing the conductor plate,was getting a po715 code,finally cleared it,now im getting PO753 ,PO758,,,PO763,,,,andPO743,which are the speed sensors in the walve body,so i was going to test the trans module and i decided to test the fuses to see if any are blown,i dont know if im getting stupid with old age or what,ive worked on cars and bikes all my life and never seen this,almost all the fuses are showing no power,i checke the other box same thing,is there something im missing,i cant believe that theres no power everything in the car works,i pulled fuses and went to the source right to the connectors themselves ,no power ,what the hells going on
 

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Do you know which fuse powers the transmission module ? How did you test it ? with the key in position 2 ?
 

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Discussion Starter #3
i actually did some reading ,i guess alot of the fuses only have power when in use,ill be thsting the tcu in the morning hope i can find the problem soon,getting mad ive done all this work and still junk,if i cant fix this its going up for sale
 

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It appears that you have a problem with the supply to the solenoids from the TCU. Possibly a bad connection in the transmission plug adapter (aka pilot bushing), or at the TCU. Make sure that the adapter is free of ATF and no pins are bent / broken. The supply to the solenoids: pin 6 at the adapter and pin 38 at the TCU.
 

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Discussion Starter #5
thank u,doing that today,dont think its the adaptor,its brand new, im thinking tcu might be bad, i had no trans codes at all,i replaced the injectors,and wires,car started to run alot better,then the trans codes popped up,i had no other codes other than the po715 code,we cleared that code out,then these 3 other codes came up so im getting frustrated with this
 

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Do you have a scanner that can access the TCU directly through the 38 pin diagnostic port (like MB SDS clone or Autel, or Foxwell or Snap-On? You need to clear codes in the TCU as well as in the ECU. Then check if any of the codes come back.
 

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Discussion Starter #7
man you have no idea how much i appreciate your help,i cleared the po715 code through the tcm,after that i got po753,,,po758,,,po763,,,and po743,,,all shift codes and torque converter pressure im guessing, i installed a new conductor plate with adaptor fitting ,i saw no evidence of oil in the adaptor plate,im a bit confused as to how to test the solenoids through the tcm harness,also the voltage,voltage im not to screwed up on ,in the books i have it says chk r with the harness disconected,so im thinking harness to adapter fitting or am i wrong,also do i need to disconnect the battery for the ohm test,i know when doing this there should be no power,book doesnt say shit if i should or shouldnt,to me just disconnecting the harness from the tcm wont kill the power,this cars killing me,god i really appreciate my 66 pick up even more now
 

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Discussion Starter #9
so i remove both connectors and that will let me do ohm test,so am i correct that one connector provides voltage to the other one
 

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Pin 38 on the connector (right at the pictures at the bottom of the link) is GROUND. For solenoid resistance measurements you need to remove that connector (with key out) and identify pins for the solenoids (pins 14, 15, 16,17, 36,37) . Then measure resistance.between each of these pins and pin 38 (ground).

For solenoid voltage item 3.0 in the list), you need to put the key in position 2 (run), and with the connectors installed measure voltage between pin 30 (left connector in the picture) and pin 38. You must either do back-probing or pierce the wiring with needles. The connectors must be installed.
 

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Discussion Starter #12
thanks again ,ill get this fixed or die trying,i got a 500 sec too,i think im a masochist
 

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I sent you some diagram in private message (conversation). Click your symbol on the right top next to 3 dots, and select "conversation".
 

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Discussion Starter #14
Well i did all the tests today and now I'm just plain disgusted,I have no resistance readings or voltage readings at all so I guess that explains my shifting problem so I'm at a loss as this point I don't know which way to turn
 

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If you identified the correct pins on the connector, and measure the resistances toward the transmission with no resistance readings, then the next step would be to test the cable. You need to identify the sockets on the connector at the transmission side and apply jumpers (one at a time) . For example, put a shorting jumper at connector sockets (at the transmission side) between pins 6 and 13, and measure resistance at TCU connector pins 38 and 14. You should see the short (almost zero resistance). If you do the tests for the other solenoid connections you would be verifying the cable harness. If there are no issues with the tests (likely) then the problem is with the conductor plate connections (on the plate) or connector itself).

It is likely that solenoid power wire (end to end) has a disconnect somewhere. check the connectors (pin 38 at the TCU side, and socket 6 at the transmission side of the harness.
 

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Well i did all the tests today and now I'm just plain disgusted,I have no resistance readings or voltage readings at all so I guess that explains my shifting problem so I'm at a loss as this point I don't know which way to turn
There is no such thing as no resistance. It is 0 ohms, short circuit, specified value 3-4 ohms or open circuit.
 

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Discussion Starter #17
there is zero,i tried 3 different multimeters,no reading on anything i dont understand that,it says to me no connect fro tcm to trans
 

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Witek is saying that a zero reading = short circuit = no resistance. Typically you read a leftmost "1" on the display when the leads are not touching anything ie. open circuit. If you used an analog meter, the needle will move with any resistance reading. Just to clarify the terminology.
 

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Discussion Starter #19
i use meters all the time,im in the HVAC field, i used 4 different meters i have no reading ,not even a blip on the meters so at this point im kinda looking for direction, what do u think would be the best plan of attack,im thinking remove the adaptor at the trans and do continuity tests trhough the wires ,are there ground wires i should be looking for that are off and are there any other things i should be lookig at,thanks again
 

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Check your conversation (private message). I sent you a diagram for the connections between the TCU and the conductor plate.

There are no grounds. The ground potential is applied by the TCU to any solenoid connection to energize the solenoid.

To test the cable harness, you need to remove the TCU connector for the harness, and you need to remove the cable connector at the transmission cable adapter end. Then follow post #15.
 
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mrboca
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