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655 – AL TecJet Comm Lost
Red alarm.
Associated parameter 1.4540.996
Cause
Corrective action
CAN bus communication for gas
control valve faulty (alternatively,
a stepper motor with gas mixer
can be installed).
1. Check cabling (→ Page 227).
2. Check power supply.
3. Carry out restart of ECU, EMU and gas control valve.
4. Check settings with device-specific dialog software (XD11).
656 – AL ProActA Comm Lost
Red alarm.
Associated parameter 1.4550.096
Cause
Corrective action
CAN bus communication for
restrictor flap A faulty.
1. Check cabling (→ Page 227).
2. Check power supply.
3. Carry out restart of ECU, EMU and restrictor flap A.
4. Check settings with device-specific dialog software (XD50.1).
657 – AL ProActB Comm Lost
Red alarm.
Associated parameter 1.4550.196
Cause
Corrective action
CAN bus communication for
restrictor flap B faulty.
1. Check cabling (→ Page 227).
2. Check power supply.
3. Carry out restart of ECU, EMU and restrictor flap B.
4. Check settings with device-specific dialog software (XD50.2).
658 – AL NOxA Comm Lost
Red alarm.
Associated parameter 1.4560.096
Cause
Corrective action
CAN bus communication for NOx
sensor A faulty.
1. Check cabling (→ Page 227).
2. Check power supply.
3. Restart ECU.
4. Replace sensor (→ Page 33).
659 – AL NOxB Comm Lost
Red alarm.
Associated parameter 1.4560.196
Cause
Corrective action
CAN bus communication for NOx
sensor B faulty.
1. Check cabling (→ Page 227).
2. Check power supply.
3. Restart ECU.
4. Replace sensor (→ Page 33).
164 | Troubleshooting | MS150116/04E 2018-04
TIM-ID: 0000038612 - 004