Hi all hope someone can help ..my wife was driving the Alphard ...2.4 petrol auto ..she was going up a steep bank overtaking a slow lorry when the engine revved as if it was on kickdown and she lost all drive luckily she managed to coast into a pull in and now the engine is dead ..turn the key and it just clicks ..there's oil water etc ..is this an engine or gearbox issue ...thanks ..Andy 

Possible speed sensors there is 2 on the transmission both the same part no. These alter the gear change 1st one does 1 and 2 gear change 2nd 1 3rd and 4th get ir read with diagnostic