1. Model: Hitachi ZX170LC-5A
2. Anomaly investigation:
Phenomenon when the speed sensor is bad:
(1) There is no change in the speed when the walking switch button is pressed, but the computer display changes.
(2) Press the throttle to actuate, but the computer does not display.
(3) When the voltage is not boosted, the computer does not display.
(4) The walking alarm does not sound.
(5) The soft/hard switch cannot be switched.
(6) The boom descending delay function does not work (the boom is very shockproof when the boom is lowered).
7) The boom descending stroke limit does not work.
(8) It cannot be adjusted automatically.
3. Analysis of the cause of the failure:
When the above phenomenon occurs, investigate the cause according to the following content:
(1) Use self-investigation to read the number of engine revolutions. Even though the engine is rotating, it is still indicated as 0003-the number of revolutions sensor circuit is bad.
(2) Please confirm the contact state of the connector of the speed sensor part, the connector of the through part of the cab floor and the connector of the controller.
(3) Please measure the single resistance value of the resistance value of the revolution sensor. Normal value is 2.3 kQ
(1) If the joint of the joint is defective, apply adhesive and then check again.
(2) If the resistance of the speed sensor is bad, replace the speed sensor. When installing the speed sensor, adjust the gap of the connecting rod gear.
