Did the car make a whining noise that changed from when you shifted
into a gear?
The noise may have been very slight.
The TCC solenoid is not the only componet that can cause a P1870. As
already mentioned a spool vavle in the valve body could also be a
cause, or the torque convertor to turbine shaft seal or the torque
convertor itself. Now if there was a whine that changed when shifting
from park or neutral to drive or reverse,
you could have a drive sprocket support bearing that has failed. This
will require transaxle removal dissassemble and repair.