2.0 hdi Automatic appears stuck in 3rd....

[jlmacd]

And so it begins......
Just as I was remarking on how much I was enjoying the new driving experience with a first time automatic, this morning it decided to not be - - automatic that is !
I set off on a 75 mile journey but within about ten minutes discovered the gearbox wouldn't shift up to top gear. Seemed to be stuck in third gear only.
I have just read a very similar post to my query and there are suggestions of changing transmission fluid or valves(?) The transmission fluid I dearly want to change anyway - as I have mentioned elssewhere on the forum - but can't get around to it soon due work commitments.
There was also mention of a message coming up saying 'Automatic Gearbox Fault' and the S and Snow buttons flashing (I assume they mean on the instrument panel) but, to be honest, I didn't notice either of these.
Does anyone know of anything I could try first, in the meantime, untilmi can get the transmission fluid changed? Would really appreciate any insight or help....

Many thanks

[steve_earwig]

Not that I know much about automatic transmissions... Stuck in 3rd could possibly be the gearbox's safe mode - my Senator came like this (turned out to be a duff selector switch).

I thought it meant the snow and sports lights on the switches themselves (next to the selector) so if they're not flashing maybe it's not that. Or maybe the bulbs have blown if you've never seen them lit up (stranger things...)

Disconnect/reconnect battery? Following the correct procedure (shut down car, roll up left trouser leg, wait 3 minutes for the BSI to go to sleep etc.)