By pixels I assume you mean the DIS and by speedo I assume you mean the dash cluster...
If its not showing anything other door opening then chances are its just switched off so press the button on the stalk to turn it back on...
As for the other clusters... unless your ECU is immo defeated then they will light up but won't run the engine... the other thing to be aware of is that swapping the cluster to test will also potentially require the radio code to get the radio running again as 2001 and on cars use the dash to store the pin so that you don't need it if you remove the battery for any reason... swapping to another cluster typically resets this and the readio will ask for the PIN again so make sure you have it handy if you try this
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