Transmission won’t shift.

altide8

Member
Agreed: if you over-tighten that little screw you can crack the plastic around the insert on the conductor plate. Not fun...

Dropping the pan and valve body is not without risk, but if you have a clean place to work it’s a straightforward process. You will want a torque wrench for the many bolts that clamp the solenoids and valve body together... 71 INCH pounds if memory serves?

-dave
I think it’s around 8nm so yeah 71 inch pounds sounds right.
 

altide8

Member
So I replaced the transmission plug this afternoon. The only code I am getting is the p260f (overvoltage) This is the first time I have been able to clear the code and change the gears with the shift. I put it back in park then to drive again and it would not let me change gears anymore. Ran the codes again and sure enough, 260F is back.
 

jrod5150

Well-known member
So I replaced the transmission plug this afternoon. The only code I am getting is the p260f (overvoltage) This is the first time I have been able to clear the code and change the gears with the shift. I put it back in park then to drive again and it would not let me change gears anymore. Ran the codes again and sure enough, 260F is back.
You could pop the electrical side of the connector out quick to make sure you did the job correctly and it’s not sitting in oil
 

altide8

Member
You could pop the electrical side of the connector out quick to make sure you did the job correctly and it’s not sitting in oil
Agreed. I think I’m going to do that when the rain lets up. Also can the supply voltage be checked when idling? I assume it can since the code is being thrown when idling. If the voltage coming into the trans is abnormal then I can assume I can look elsewhere. Tcm or charge system.
 

Nautamaran

2004 140” HRC 2500 (Crewed)
If you are seeing 13.2 to 14.4 volts the alternator is probably fine and you should look at the TCM (unfortunately)

The sensors probably operate at 5 volts, and the TCM will have an internal regulator that supplies that 5v to the conductor plate (and other internal components).

A used TCM is an option, though you’ll want to use a dealer-level tool to reset the adaptation values that control smooth shifting.

-dave
 

altide8

Member
So I was not fully sure how to test the voltage of the pins that are going into the transmission. I unplugged it and then started the van. I was barely getting any voltage on each pin .05??

More importantly. There was a little fluid on the plug. I cleaned it off, plugged things up, cleared the codes and they actually stayed gone. I did a test drive and all was well. I was able to shift manually and the van was changing gears normally. So does this mean the overvoltage code was because of the plug? Or could the tcm work at times then not work? I ask because, before it got dark I went out to check again and the 260F code was back.
 

altide8

Member
You could pop the electrical side of the connector out quick to make sure you did the job correctly and it’s not sitting in oil
I think you are on to something. There was a little fluid on the plug. I guess I did not do the job correctly? It definitely seemed fully seated. Although I took it easy on the screw.
 

altide8

Member
I cleaned the plug again and for the last 2 days the transmission has been shifting normally. No driving issues. No lights on the dash. I can shift manually. Although a 200a transmission code is stuck on? Anyone ever ran into this?
 

Bobnoxious

GONE FISHING
Depends on status of code, active, pending or stored? Codes can self clear.

Is the CEL on?

How's performance?

Sounds like a new connector seal.
 

Bobnoxious

GONE FISHING
Don't worry about it.
 
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