Hello,
I was driving on the freeway with the transmission switch in "Sport" mode going about 60 MPH when I decided to pass the vehicle in front of me. When I pressed the accelerator down, the car made a loud bang but it did accelerate to 70 MPH. At that point the GEARBOX FAILURE warning illuminated on the dash. The car seemed to drive OK but when I slowed while leaving the freeway, it seems like it does not go into low gear; perhaps it is starting in second? I checked the OBD code and got the P1747 Pressure control solenoid A: short circuit reading. I have a diagram the shows the resistance across these solenoids to be 6-8 Ω but I have not measured them at this point though. In looking up the warning and reading various repair manuals and diagrams for the 5HP-24 transmission, it appears the solenoid is relatively easy to replace. If in fact the solenoid is shorted, is there any reason to think that replacing it would not fix the problem? Perhaps changing it and the Pressure Regulator Valve at the same time may be prudent?
The car has never had a problem shifting or made any indication that there was a problem with the transmission prior to this happening. I do have a spare transmission available if this one is actually broken but I'd prefer not to have to deal with replacing the whole unit. Any advice on the best course of action would be most appreciated! Thanks much. Dave

 

P1747 is PRESSURE REG #3.Here is some info for controls and DTCs.

 

Thanks bunch Motorcarman! Much appreciated.