04 3500 P0973 transmission failure

[RAB]

Driving home last night, pulled away from an intersection when CEL came on. Pulled right over checked everything and proceeded down the road, trans seems stuck in 2nd or 3rd gear. CEL was P0973. found oil on and in plug on drivers side of trans. After checking fuses, cleaned plug, checked fluid code will not clear. Truck is stock with 120K miles, no previous issues. Would like some knowledge before I take it trans shop. Thank you in advance.

 

[cerberusiam]

P0973 Transmission Overdrive Circuit Voltage Too Low



Its going into limp mode because the ECU is seeing a problem on the OD solenoid circuit. That could be a bad connection due to the oil in the plug and connector. Make sure you get that cleaned out good with electrical contact cleaner and see if that will help. If not, probably the solenoid control harness or solenoid gone bad.

 

[JJPage]

There is a TSB out that sag2 posted awhile back. It stated to replace the gear selector sensor if contaminated with trans fluid. I was able to clean mine out with an arasol cleaner, I then coated with dielectric grease and plugged back in. Between that and a new APPS, no more problems.



I should also state, that you have to find and repair the source of the fluid leak. Mine was originating at the front band adjustment stud, I was able to use thread sealant and a copper washer to stop it.



Jess

 

[outlaw1sammy]

My truck also has fluid in that plug. Is this a common issue? The transmission seems to work as advertised, except for the occasional 1-2 hunt under light throttle. I will have to look up that TSB as I have a fluid flush to do on it any way and will take a closer look at that time?