it's a jeep, 2005, with a 722.6 trans. i've not compared tcm diagrams with jeep and mb, so pin numbers maybe are not relevant, but i could make sense of this mess if i could find actual values for it. grasping at straws. having done a few if these on mbs, i've never had a problem.


P0657 — Actuator Supply Voltage "A" Circuit/Open
P0710 — Transmission Fluid Temperature Sensor "A" Circuit
P0717 — Input/Turbine Shaft Speed Sensor "A" Circuit No Signal

Replaced conductor plate and connector. P0657 sets with key on, p0710 and p0717 when driven in limp home-2nd gear. Clear key on, eng off and p0657 never clears.

pulled connector from trans, pin 6 is supply to solenoids, should be 12v, shows 3.7v. The other 11 pins show a range from 3.6 to 6.0v, including pin 12, which is the ground for the sensors. 1 of these is supposed to be 6.0v.

pulled tcm, expecting atf intrusion-no. Tcm has 12v to pin 29 and ground to pin 30. Output to trans is 3.7v from tcm pin 38. Likewise, all other pins on the output side of the tcm show 3.6 to 6.0v, including pin 33, which is the sensor ground for the trans.

looking for a voltage chart for each circuit on the output on the tcm. I did find the temp sensor and atf float are supposed to get 6.0-I forget where I found it and which pin. The atsg 722.6 book has some voltage and resistance numbers but not all. Tcm pins 12 and 35 are speed sensor inputs from the trans.

Removed circuit board from case and found no burns or signs of atf. My suspicion is the tcm somehow got fried. In the process of building a breakout harness for this job.

Thanks, chuck.

Does the plate ohm out OK when you check a trace line? Ive had an aftermarket plate ride circles around me on a W210, it was the stupid plate.

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2012 BMW X5 (Beef + Granite suspension model)

1995 E300D - The original humming machine (consumed by Flood 2017)
2000 E320 - The evolution (consumed by flood 2017)

this jeep is gone. My haste in trying to do a job I've done a few times before made it worse.

I found a chrysler training manual for this trans and it specified that the tcm will drop voltage to trans pin 6 when it sees no signal return. Assuming the tcm had 12v going in and the trans needed 12v to it was my mistake. I surmise the intial p0657 was due to to the abundance of atf in the connector, which I had cleaned numerous times before reassembly. I did take the extra step of building a harness so I could bench test the valve body before putting it back in. Once I proved that 12v made the solenoids work, it went back in and no problems after. Thanks for the help.