The possibility of the coolant in fluid but no fluid in the coolant is unlikely, the lower pressure in the cooling system pushing fluid into the transmission cooler when the engine is shut off and transmission main pressure and cooler flow drops, is less than the cooler out pressure. Most likely water from a missing or loose dipstick. The code 14-12 relates to oil level sensor fails low out of range, and can be caused by a very low fluid level, the HD transmission can run very low on fluid and set codes and shift poorly due to the low level. "The record in our shop was a dump truck that was driven in low 5 gallons of fluid low, barley moving at all". The code that has me worried is the code 46-27 ,this is almost always caused by a failed high side driver in the ECU itself, they need to swap an ECU from a sister truck in to be sure, but a bad ECU is most likely the cause of the no range condition.

Thanks for requesting me!
Bill

There is an integral cooler available on some HD models that can leak and cause coolant to enter the transmission, However the coolant usually causes other codes related to shorts and will effect more than just the solenoids driven by the A solenoid driver in the ECU. The code they have is for over current to just the A driver solenoids. If there truly is coolant in the fluid then a complete change out of all frictions and solenoids would be necessary. The truth will be known if they come back to the customer and tell him that the ECU was also bad, they wont do this until they have overhauled the transmission and the 46 cod is still active. Ask them to send a fluid sample to have it tested,if you feel the fluid did not look like it was contaminated. Remember synthetic TranSynd looks tan when water contaminates it.

Bill