Will it run the pump at all without connecting up your hose reel?
What happens to the little green light when you switch the pump on? Does it change colour?
My first thought would be to look at the dead end setting as that could have been lost somehow.
Switch controller on, press both + and - buttons at the same time for 3 sec. A number should come up. Press both + and - button again for another 3 secs and the figure will start to flash. Press the + button until the figure gets to C and then switch the controller off to reset the dead end to C. (The figures will start at 1 to 9 and then change to A to F I think. C is the factory setting.)
Tell us what the figure was before adjust it.
Another thing I would test is the Varistream and pump together from a cable from the van battery. If you are using a auxillary battery it may have enough power to run the pump, but the Varistream shuts the system down if the volts are lower that 10.3v.
It could be either a flat or dead battery or even a faulty connection between the battery and the Varistream. Fuse holders are prime suspects for bad connections.
Have you reversed battery polarity when connecting the battery up by mistake. If you have then the controller will be fried.