Do the van shut off when u take d cable off

Hello, you should never disconnect the battery while the engine is running. It can definitely stall depending on conditions. The engine and all the related processors and electronics are meant to operate with a constant amount of reference voltage from the battery, and if you remove the battery cable, it will not operate properly, regardless of whether or not the alternator is functioning properly or not.

The alternator charging test you are referring to was ok to try back in the 1970’s - that’s not the case now! Removing the battery cable while engine is on can damage the sensitive electronics of today’s vehicles - the alternator will have no where to send the voltage. Without more boring details > DO NOT REMOVE THE BATTERY CABLE WHILE ENGINE IS RUNNING! Charging system can easily be tested using a simple volt meter.