Indication on LDU
Possible cause
Procedure
SCR CAN failure
SCR system does not receives CAN
signal.
•
Re-establish the cabling of
X24-5/6 to the MCM E70.
NOTE:
This is only applicable
to SCR systems with
CAN interface.
Communication to ECS fail
ECS does not receive CAN interface
signals.
•
Re-establish the cabling X34-5/6
to MCM E70.
For WECS:
•
Re-establish the cabling CAN-M
X22-55/56 to FCM 20.3.
For UNIC:
•
Re-establish the cabling CAN 3
X21-2/3 to LDU-20.
CAN interface failure LDU
ECR
CAN interface failure to LDU ECR.
•
Reboot the LDU local and LDU
ECR.
•
Re-establish the cabling CAN#2
X22-5/6 to the LDU local E71.
•
Re-establish the cabling CAN#3
X21-2/3 to the LDU ECR E72.
Tab 10-65 Urea dosing failure
Indication on LDU
Possible cause
Procedure
Urea dosing system Setpoint
failed
Status bit for hardware signal failure:
Urea dosing setpoint.
NOTE:
This failure can occur due
to short circuit or wire
break.
•
Re-establish the wiring between
E70 and external dosing system.
Urea feedback input failed
Status bit for hardware signal failure:
Urea feedback.
NOTE:
This failure can occur due
to short circuit or wire
break.
•
Re-establish the wiring between
E70 and external dosing system.
Dosing system not ready
SCR system sent a signal that urea
dosing system is not ready.
•
Do a check of the external SCR
control system.
Tab 10-66 Temperature sensor failure
Indication on LDU
Possible cause
Procedure
TE3746C
Temperature sensor fails to mea-
sure the exhaust gas temperature at
SCR reactor outlet.
Status bit for hardware signal failure:
Temperature sensor TE3746C.
•
Re-establish the cabling X41-1/2
to MCM E70.
•
Replace the faulty sensor if re-
quired.
X72-B
AA00-0000-00AAD-410A-A
Operation Manual
LP SCR - Alarm failure troubleshooting
Winterthur Gas & Diesel Ltd.
- 463 -
Issue 003 2021-12
