What does it mean?
P1796 is a Powertrain (engine, transmission, fuel system) fault code. It indicates: A/T Additional AutoStick Input Circuit Malfunction .
Symptoms
- MIL (check engine lamp) is on and the manual shift function cannot be selected or is ignored
- The gear display does not change when up or down is requested
- Unexpected shifts or the transmission staying stuck in one gear in manual mode
- Normal automatic operation may feel completely unaffected
- The gear position display may flash or show dashes
- The fault often returns as soon as the manual gate is used again
Likely causes
- Worn or failed up and down shift contacts in the selector gate or on the steering wheel paddles
- Liquid spilled into the centre console, corroding the switch and its connector
- Open or shorted wire between the switch and the transmission control module
- Loose or corroded connector under the console or behind the selector assembly
- Broken clockspring circuit on vehicles with steering wheel mounted shift controls
- Selector assembly out of adjustment or a broken detent mechanism
- Control module input circuit fault
How to fix it
- Watch the up and down switch states in live data while working the gate or paddles through their full travel
- Inspect the console and selector assembly for spilled liquid, sticky residue and corrosion
- Check the switch contacts for continuity directly at the switch connector
- Test the wiring from the switch to the module for continuity and for shorts to ground
- On paddle systems, check the clockspring circuits for continuity with the wheel turned to different positions
- Replace the switch or selector assembly once the wiring is proven, then verify every request registers