In my Nissan Micra K11 dashboard, the backlights for the clock and left-hand side of the speedo have stopped working. The dashboard is similar to the one pictured below, with the central clock and fuel/speedo/engine temperature gauges, no rev counter.

What bulb(s) do I need to repair them, and do they need to be all replaced at the same time?


Question: Does changing the gap between plates change the capacitor voltage?
Answer: The electric field between two parallel plates of area \$A\$ is roughly \$E = { Q \over \epsilon A} \$, hence the voltage at a distance \$x\$ apart will be \$V(x) = { Q x\over \epsilon A} \$.

So, doubling the distance will double the voltage.

The electric field approximation will degrade significantly as \$x\$ gets larger than some fraction of some characteristic dimension of the plates.