As I understand it, this little beauty controls the ECU and fuel pump amongst other things, it also frequently fails which means you turn over the van and it sounds like it should start but it doesn’t and eventually the battery dies.

The visual giveaway is no coil lights on the dash, if you see this, stop trying to start the van, go to ebay, buy a new relay and you’re all good, I didn’t and flattened the battery many times, worked fine after I replaced the relay.