Diagnostic & Troubleshooting; Diagnostic; Example On Resolving A Fault; Solution - Danfoss pved-cl Operation Manual

Operation Manual
PVED-CL Controller for Electro-Hydraulic Steering, Version 1.38
Diagnostic & Troubleshooting

Diagnostic

Troubleshooting

Typical Fault Sources

© Danfoss | May 2016
Any detected fault will bring the PVED-CL in reduced state or fail-safe state. Fail safe state infers that the
magnetic bridge is disabled and no pilot flow from the PVED-CL controls the valve. A fault that brings the
PVED-CL in fail-safe state is denoted a 'critical' fault. All critical faults are stored in the PVED-CL error
buffer for diagnostic purposes.
The PVED-CL may be accessed via CAN for diagnostic purposes while being in fail-safe state but
parameter configuration is not possible in fail-safe state. If the fault is related to the sensors or CAN bus
cable tree, these faults should be resolved and the PVED-CL should be powered up again. If the fault
requires parameters to be changed, the user must bring the PVED-CL in calibration mode (or operational
or reduced state if possible) before re-configuring the parameters.

Example on Resolving a Fault

A sensor is mapped (see Mapping a Steering Device
system. The sensor cannot be unmapped because the PVED-CL enters fail-safe state when powered on.

Solution

The PVED-CL needs to run in operational, reduced state or calibration state before any parameter may be
changed i.e. a) Simulate the sensor signal to satisfy the PVED-CL sensor checks while changing the
parameter or b) power up the PVED-CL in calibration mode.
The PVED-CL software performs diagnostic checks on the CAN bus interface, analogue sensors, magnetic
valve bridge interface, internal hardware peripherals and software execution plausibility. All detected
faults, which are rated as safety critical, will bring the PVED-CL in to its fail-safe state. Secondly the
diagnostic checks provide precise indication of the fault source and thus reduce system down-time.
However, not all unexpected system behavior can be traced via error codes. E.g. a too low gain-related
parameter value may result in too slow steering actuation but this cannot be detected as a fault. To rule
out faults resulting from conflicting system and parameter settings, the following trouble shooting steps
are recommended:
•
Check the list of typical faults first
•
Check the J1939 Diagnostic interface
•
Check the PVED-CL LED diagnostic interface (see
The table below contains symptoms and possible resolutions. The PVED-CL operation status is the status
reflected in the CAN OperationStatus message (see PVED-CL Communication Protocol Technical
Information, 11079551), which is transmitted periodically on the CAN bus. If the PVED-CL operation
status is not available on the CAN bus, check the LED diagnostic interface see
106).
on page 31) as present but does not exist in the
LED Diagnostic on page 106)
LED Diagnostic
11025583 | AQ00000216en-US0302 | 101
on page