Based on the names of the variables, it sounds like you are talking about the signals (ie wires). When you placed the test points where did you place them? If you want to see the ports on the block Vehicle Dynamics then the test point should be placed at the top-level on the signals that come out from the block Vehicle Dynamics. SIT lists signals based on their source (there is only one source and possibly many destination), which is why you want to place the test point on the signal that has the port as a source. If you place the test point inside the Vehicle Dynamics block you will ensure that the output from one of the internal blocks (possibly the block m/s to km/h) can be probed.
If this doesn't work, then one thing you can try is to place a gain block (with a gain of 1) between the Vehicle Dynamics block and the destination of the signal. This will allow you to probe the signal coming out of the gain block even if you can't probe the outputs from the Vehicle Dynamics block directly. It should not be required to add a gain block, so if you find yourself needing to add a gain block let us know. Especially if you can share a model (or reduced version of a model) that would be great.
Carl LNational Instruments
As I said before, parameters (and variables) are mapped to controls. Parameters (or variables when using inline parameters and setting tunable variables) are items that can be changed by the user while the simulation is running, which is why they are mapped to controls. They are not changed by the simulation, but can be changed by the user. So if you want to know the initial value then you could still use a control and map the variable/parameter, since we set the value of the control to be the value of the parameter it is mapped to when the simulation starts. If you want to make sure you don't accidentally change the value you can disable the control.
The other type of variable you might be talking about are the variables you write to when using the To Workspace blocks. In this case you can not directly read or write the variable (they are not updated until the end of the simulation). You can however probe (as you have just done) the signal going into a To Workspace block or a signal coming out of a From Workspace block.