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

Check 3-6: Neutral Indicator Light (LED) Inspection
Meter Unit Circuit (ZX1000J Model)Main Throttle Sensor Output Voltage Inspection
Measure the output voltage at the main throttle sensor in
the same way as input voltage inspection, note the following.
Disconnect the main throttle sensor connector and connect
the setting adapter [A] between these connectors.
Special Tool - Throttle Sensor Setting Adapter: 57001
-15 ...
Front Fork Removal (Each Fork Leg)
Loosen the front fork top plug [A] beforehand if the fork
leg is to be disassembled.
Special Tool - Top Plug Wrench (45 mm) [B]: 57001-1741
NOTE
Loosen the top plug after loosening the handlebar
clamp bolt [C] and upper front fork clamp bolt [D].
Remove:
Upper Fairing Assembly (see Up ...
Valve Installation
NOTICE
Do not lap the valve to the valve seat, using the
grinding compound. It will come off oxide film
treated surface of the valve.
Replace the oil seal with a new one.
Apply a thin coat of molybdenum disulfide grease to the
valve stem before valve installation.
Install the springs so ...