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

Check 3-6: Neutral Indicator Light (LED) Inspection
Meter Unit Circuit (ZX1000J Model)Air Cleaner Housing Removal
Remove the fuel tank (see Fuel Tank Removal).
Disconnect the secondary fuel hose [A] from the delivery
pipe of the nozzle assy [B] (see Fuel Hose Replacement
in the Periodic Maintenance chapter).
Disconnect the secondary fuel injector connectors [C].
Free the lead from the grooves [D].
...
Fuel Filter Cleaning
The fuel filter [A] is built into the fuel pump and can not be
cleaned or checked.
If the fuel filter is suspected of clogging or being damaged,
replace it with the fuel pump as a set.
Fuel Pump Circuit
1. Ignition Switch
2. Engine Stop Switch
3. Joint Connector E
4. ECU
5. Engine G ...
Oil Cooler Installation
Replace the O-ring [A] with a new one.
Apply grease to the new O-ring.
Install the water hoses and hose clamps [A] as shown in
the figure.
Water Hose (About 300 mm, 11.8 in.) [B]
Water Hose (About 130 mm, 5.1 in.) [C]
Yellow Paint [D]
Tighten:
Torque - Water Hose Clamp S ...