l was told that by switching the ignition off on off on within 5 seconds of turning it on I'd see the check engine light blink. l counted the blinks as instructed and it gave me the code: 1 pause, 2 pause, 4. Anyone know what this means? All my transmission fluid leaked out and l would like to know what this code specifically means.

Yor van is a 1995 or older l assume. those years are a 2 didget codes.. try it again. all 12 means is that the codes were checked recently.

Key cycle codes typically only work on 1995 and older vehicles with OBD 1 systems. For transmission specific codes the TCM (Transmission Control Module) will have to be scanned and codes extracted directly from it. The PCM will show only that the TCM contains a fault code.
If all the fluid leaked out, you likely have a seal or gasket, or cooler line leaking severely.