Auto D4 Light Flashing

[Rid]

I've just changed the block to heater valve hose on a 98 Odyssey 4 cylinder. When I start the car up the D4 light continues to flash and if I try to put the car in gear it does so with a worrying thump. I haven't touched anything around the transmission so I assume I've disturbed some sensor (?) or other. Can anybody help ?

[Rid]

When doing the hose, I disconnected a couple of electrical connectors to give myself a bit more room. Today I split them again and cleaned up the terminals. Did seem to be a bit of dirt on one at the front of the block. Re connected and all is now fine.