if your shifter has an "implausible" input from the touchshift, it will disable the touch-shift. NOT saying this is a likely circumstance ... just saying that this will happen. The cause for this that I have seen is either up or down (in the touchshift part of the shifter) is shorted to ground, Normally, activating up,+ or down,- shorts that line to ground ... that is how that circuit works HOWEVER, when this is done while the shifter in NOT in DRIVE ... it can disable the touchshift until the next time you restart the car.

no simple way to detect this without hooking the car up to a star tester or reading the voltage at the switches (both are at 5vdc when open).

a foreign object may have made its way into your shifter and is shorting out one of the switches. wont say its the only way this would happen ... just the only way i am aware of .



OR, if the fingers in the down (-) switch have broken or are no longer making contact (when shifting down) this would also cause this same issue ....




I cant find a picture of the "fingers" of these switches, but here is the contact plate that they slide on completing there respective up and down circuits ...




swapping in another shifter or inspecting the internals of this one are what you are likely going to have to do.

Chris