Chrysler 300M setting a PO750

I have a Chysler that is setting this code PO750. Lo/Reverse Solenoid. I have used a scope and all four solenoids are giving me a good spike and are working properly. But still sets this code at every startup. Does anybody know what the perameters are to set this code, or has anybody worked with this condition?

Oh yeah we replaced a the tranny because of bits of washers in the pan. but the same code is still there. even after a relearn

Going from the code error it sounds like the issue is with the wiring between the solenoids and the ECU rather than the solenoids themselves since the code is for a circuit failure. Make sure the wires to the solenoids are making a good low resistance connection between the points they run to and they are not making any bridged connections to something else they shouldn’t tie to like ground or power.

If the vehicle is operating properly, a one inch length of black tape will solve this problem…

I’m with Cougar. If this was happening on the original transmission and still on the next one you put in then you have a wiring harness or ECU problem. There is an outside chance that both of these transmission have the same problem - maybe search the web for whether or not this particular solenoid is prone to failure. But in general I’d stop looking at the trans unit itself for a while

Thank you for replying!! The thing is, that I have seen the voltage on an Ease oscilloscope. and it does not appear to have any connection problems with the TCM. All of the solenoids cycle, what appears to be at the right time and at the right voltage. I have ohmed the solenoid also, and it is 1.9 which falls into the 1.0 and 2.5 frame. It appears that the tranny is working very well. Anybody know where I could get a Chrysler hydraulic schematic? Chrysler does not provide that. Funny because Ford and GM do!! maybe thats my ticket

If you feel the correct signals are making it to the ECU ok then the trouble may be with the ECU.