Your van will not start nothing happens when you turn the key on battery is fully charged and have power only going to the horn and headlights?

You may have a bad starter solenoid. You did not say what type of van this is; location can vary. Check power to the keyswitch. If there's power IN, be suspicious of the keyswitch itself. you may also want to check yhe neutral safety switch. if you play with the shifter move it up and down and when you put it on park again the van turns on you have found your problem.also try putting your vehicle in neutral check if it works. when neutral safety switch is bad the symptoms would be, nothing happens when the key is turn.. this is the same symptom for the starter relay problem. try a headlight start test. turn on your headlights, try turning your vehicle on if the lights stay bright you may have an open in the starting system. if the lights dim you may have a shorted starter solenoid or a bad ground.