Speedo out-not reading correct!

[locky]

Just fitted digidash(yes this thing again) and its reading double if not more the speed! how do i get it to read the correct speed?
Thanx in hand

[jim sri]

im not 100%sure but i think u may be using the wrong gearbox sender.did you remove the dash/sender yourself fdrom the astra gte or someone else?removing it yourself is the best way of gettin the correct bits. i think vaux made 3 differnt senders for this dash, each has a different letter(s) written on the sender bit that goes in the gearbox, clean the snder and u shud see what letter one youve got, then try and salvage differing ones from another astra gte.

[mikeoxford]

BEFORE spending and money on new senders

get your dash back out and flick the red siwtch on the top over

see if that helps at all

its in the centre on the top - just behind the lip of the front plastic case

[locky]

Iv tried flicking the switch on top and changing it from km to mph, my dad is bringing me home various senders tomorrow to try!
The sender i put in had a square "prong" in the middle, i did not change the part that actually goes into the box, justwhere the speedo cable satin
Thanx 4 the help lads!

[d0gz_bollox]

my speedo is out 2mph at 120mph!!!!! super accurate

[novax]

Like Mike says.... try the switch. It's a common problem after the install it is possible it's the sender, but only if they are not from the same car originally. I think the later 16V dashes had 8 pulses per rev of the sender, not 4.