If the display function does not work, replace the meter unit.

Check 3-6: Neutral Indicator Light (LED) Inspection
Meter Unit Circuit (ZX1000J Model)Electrical Leads
A two-color lead is identified first by the primary color and
then the stripe color. Unless instructed otherwise, electrical
leads must be connected to those of the same color.
Instrument
Use a meter that has enough accuracy for an accurate
measurement. Read the manufacture’s instructions ...
Stick Coil Primary Peak Voltage Inspection
NOTE
Be sure the battery is fully charged.
Remove the stick coils (see Stick Coil Removal).
Do not remove the spark plugs.
Connect the ECU to the harness.
Measure the primary peak voltage as follows.
Install the new spark plug [A] into each stick coil [B], and
ground them onto ...
Nozzle Assy Installation
Replace the dust seals [A] with new ones.
Apply engine oil to the new dust seals, and install them.
Install the nozzle assy securely.
Push the four mounting positions of the injectors.
Set the joint pipe parallel to the air cleaner housing [B].
NOTICE
When installing the nozzle assy, ap ...