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

Check 3-6: Neutral Indicator Light (LED) Inspection
Meter Unit Circuit (ZX1000J Model)Drive Chain Slack Inspection
NOTE
Check the slack with the motorcycle setting on its sidestand.
Clean the chain if it is dirty, and lubricate it if it appears
dry.
Check the wheel alignment (see Wheel Alignment Inspection).
Rotate the rear wheel to find the position where the chain
is tightest.
Measure the ver ...
Parts Location
1. Timing Rotor
2. Crankshaft Sensor
3. Horn
4. Oil Pressure Switch
5. Rear Brake Light Switch
6. Oxygen Sensor (Equipped Models)
7. Alternator
8. Stator Coil
9. Gear Position Switch
10. Sidestand Switch
11. Immobilizer Amplifier (Equipped Models)
12. Radiator Fan Motor
1 ...
Cooling System Flushing
Over a period of time, the cooling system accumulates
rust, scale, and lime in the water jacket and radiator. When
this accumulation is suspected or observed, flush the cooling
system. If this accumulation is not removed, it will clog
up the water passage and considerable reduce the efficiency
...