Has anyone gotten and fixed this code, cant seem to find anything on this at all. I have lost my passing gear also. Passing gear comes back at different times though.

 

Found this on the diesel forum: P1799 Hold Switch Circuit Malfunction


It probably depends on the vehicle.

 

Mine says calculated oil temperature used under transmission codes in scanner. Under data it said my trans is running 1025 degrees farenheit so something is wrong somewhere. Fluid is fine and red so not burning up yet.

 

I just found this. Looks like a bad trans temp sensor:
When Monitored and Set Condition:


P1799-CALCULATED OIL TEMP IN USE






When Monitored: Whenever the engine is running.


Set Condition: The DTC will set if any of the three conditions are present. Thermistor


voltage (Transmission Temperature Sensor) out of range. Continuous erratic thermistor


voltage is sensed. Thermistor Temperature stays low for an extended period of time.

 

I will check tomorrow hopefully not part of of solenoid pack.

 

Possible causes:
intermittent wiring & connectors

speed sensor ground circuit open

transmission temperature sensor signal circuit open

transmission temperature sensor signal circuit short to ground

speed sensor ground circuit short to voltage

transmission temperature sensor signal circuit short to voltage

transmission temperature sensor - inoperative

tcm - calculated oil temp in use

tcm - transmission temperature sensor high

tcm - transmission temperature sensor low




test

 

The temp sensor is part of the governor pressure sensor.

 

Today I changed my solenoid pack and range sensor. While under truck I changed the pressure transducer, had a crack on top of it. I did a relearn after clearing p1799 code and everything went fine. The problem is I took it for two drives and still have no power taking off and no kick down in high gear. Overdrive button works when pressed off and on. I am stumped no codes at all in truck this problem comes and goes while sometimes driving it comes back but then goes away again. Parts used were mopar parts. Thanks

 

Truck is finally back to normal did a couple of relearns. I will say if you are running a 45rfe that has a solenoid with black connector update it to the white connector with new range plate. Removes any engagement noise you get when you put it in gear and
I have no hesitation on throttle at take off and passing gear is much better.