Error Message

The following message pops out when I run the model, does it mean the fourth equation in my model is wrong?

STEADY: numerical initial values incompatible with the following equations

What the message means is that when one is plugging the values declared in initval into equation (4), it results in an infinite number most likely because of a division by zero.
Remember also that if you forget to declare a variable in initval, it is initialized with a zero value.