Model is underconstrained.
The following variables couldn't be defined:
 * T in component T
 * TCa in component TCa
 * koff_ in component constants
 * N0 in component N0
 * k1 in component constants
 * F in component force
 * d/dt TCa in component TCa
 * d/dt N1 in component N1
 * d/dt P0 in component P0
 * d/dt P1 in component P1
 * d/dt P2 in component P2
 * d/dt P3 in component P3