Cautionary Instructions Before Starting Failure Diagnosis - Kubota G21LD / G21HD Workshop Manual

G21LD · G21HD, WSM
1. CAUTIONARY INSTRUCTIONS BEFORE
STARTING FAILURE DIAGNOSIS
1. Self-diagnosis function
The EPS controller has a self-diagnosis function. If the EPS controller detects an abnormal condition in the system,
it performs the following.
• Making the warning lamp go on.
• Turning OFF the motor current.
• Storing the error code.
• When the system recovers from the failure, the EPS controller automatically makes the warning lamp go off.
Depending on the position of self-diagnosis, however, there may be cases where resetting cannot be made without
turning OFF the main switch an performing fail-safe history erasing.
2. Warning lamp
• If the system is normal, the warning lamp glows for 5 seconds after the engine starting and goes off.
• The warning lamp has a function to indicate an abnormal condition in the system and to display the error code.
3. Error code
• When an abnormal condition is detected and the warning lamp goes on, the error code is stored.
• The stored code may be lost if the power of the EPS controller is turned off or the coupler is disconnected.
4. Cautions in the EPS system
• If the steering wheel is kept fully turned for a long time with the machine stopped, it may become hard to operate
the steering wheel. It is not a failure: it is caused because the EPS controller decreases the current applied to the
motor in order to protect the EPS system. To restore the normal steering wheel state, wait for about 5 seconds
and start the engine.
• When removing the steering wheel, take care not to shock the power steering assembly.
• When replacing the power steering assembly, replace it as a whole assembly and do not disassemble motor,
torque sensor, etc..
• When replacing the power steering gear case, replace it as a whole assembly.
5. Cautions in servicing
• If two or more error codes are stored, perform failure diagnosis starting from the error code displayed first (whose
flashing time is lowest).
• When performing failure diagnosis based on the error code because the symptom complained of by the customer
has no repeatability, obtain from the customer's detailed information about the conditions at the time of warning
lamp going on and perform a test under the same conditions as much as possible. If the warning lamp does not
go on in the test running, check for imperfect contact, etc. by shaking the harness or connector while following the
failure diagnosis chart.
• Do not connect or disconnect the connector with main switch turned ON.
5-S1
STEERING
KiSC issued 08, 2007 A