Error Log

Error Log

All errors are permanently stored inthe EEPROM of the steering computer. This error log has a capacity of 32 errors each with 3 error codes (error location, type, priority).

To simplify the nomination of error causes, error codes are divided into location, type and priority.

Error location and error type related to a single error:

Error location: e.g.: Angle transmitter track 1 of steering axle 1, pressure sensor,...

Error type: e.g.: Wire breakage, maximum value exceeded,...

The priority determines the way the steering system responds to an error:

Priority 0: Warning, steering is not affected. Priority 1: Axle steering but at crawl speed Priority 2: Axle steering but travel release not issued.

Priority 3: Axle blocked, travel release removed, brakes apply

Safety Feature

The steering system safety feature is designed to bring the steered axle to a safe condition in an emergency by switching off the safety outputs in the steering computer.

In this steering system “safe conditions” are defi ned as follows:

Startup

After power up as long as there is no release signal from the steering drive controller, no travel release is issued to the drive controller. No error code is displayed.

Normal operation The steering system operates without restriction. The brake is open. The drive system is released. Crawl speed is not active. Below the travel speeds recorded in P_99 the control circuit is switched to reduced level (reduced energy consumption and actuator at zero position for low axle dynamic requirements). The steering direction is inverted depending on the cab position.

Restricted normal operation for “Prio0” warning

If the CAN connection to the drive controller fails, there is not speed signal available - the switch to reduced control level is interrupted. If the CAN connection fails before a valid cab position is transmitted, the “normal” cab position is assumed - if a position has already been transmitted, the last cab position is maintained.

Medium severe error “Prio1” Restricted operation with crawl speed

“Prio2” error Truck coasts

Severe error “Prio3” Truck brakes

For Prio1 errors (failure of a steering setpoint device channel, problems with the power supply, minor control deviations etc.) where restricted steering operation is still possible, the drive system is switch to crawl speed via the CAN-BUS. If the CAN connection to the drive controller is also faulty, the travel release is removed (Prio2 error through error re-occurrence).

For Prio2 errors (major control deviations, implausible cab position signals) where limited truck steering is still possible, the travel release is removed from the drive controller. The truck coasts.

For Prio3 errors (axle inversion, excessive control deviation) where the truck can no longer be steered, the travel release and steer system release are removed and the truck brake is activated.

The ‘error memory’ menu item must be selected to read or delete the error log with the LCD display.

See “Steering Computer Operating Functions” chapter

Press ENTER to activate the error log function. The display now changes to the fi rst logged error. Press ESC to quit the error log function at any time. You can now use the PLUS and MINUS keys to read off the errors in succession. At the end of the error log (error 32) it automatically reverts to the beginning (error 1). Once an error 255, 255, 255 is displayed, no futher errors are entered in the log. The error before this is the last logged error. When the error log is completely deleted only entries with 255 are contained.

Priority Location Type Previous error Next error

Deleting the Error Log

The error log can be deleted from any display status.

Press for 3 seconds

When the PLUS key has been pressed for 3 seconds a prompt appears to delete the error log.

Do not delete Delete The ‘error memory’ menu item can now be quit with the ESC key.

Press ESC to avoid deleting the error log. The display changes back to the error log. Press ENTER to start deleting.

The progess of deletion is shown through a bar in the second line.

After deletion all entries in the error log are set to 255. The display is automatically restored to the fi rst error entry.