Yea I was a bit nervous the first time I did it just incase it never went back to normal
I have done it a fair bit now though and seems to go back fine....... touch wood though
I can't find the original thread but I did save it into a word doc so here are the fault codes and what the display will tell you.
1. All LCD characters are displayed. All gauges step up/down. Warning lights all on.
2. Fuel remaining in tank? (appears to be in litres even though its a UK car!)
3. This shows '0.0' until the car is started then a number shows that varies with throttle (Fuel flow?)
4. Fault codes. This is a four digit/letter? code. Mine showed an 'h' in the last position (_ _ _ h) and a charging fault alarm on the graphics display (in red). The digit code can be reset by pressing the Odo' reset button, the graphics display stays put though.
Once the errors are cleared, or if there were no stored faults the display just shows four dashes, ie. _ _ _ _
t = an injection fault has been stored for >4 seconds.
j = a fuel gauge fault has been seen for >100 seconds.
d = an injector signal fault has been detected.
h = an
level sensor fault has been detected.
It also looks like the letters can only appear in the sequence shown...ie. (_ _ _ h) or (t _ _ _) or ( _ j _ _) etc.. You have real issues if you see (t j d h)!
The normal display if there have been no faults is (_ _ _ _), if the dashes are flashing then this indicates a fault with the on board computer...!
Thank you to the writer of the original thread.... that I can't find
EDIT: thread found Renault Laguna II - Dashboard diagnostic