U1139

CD8B - U1139

Information saved in
DME

Fault code
CD8B - U1139

Fault text
Idle actuator bus off / SMG CAN

Fault description


Condition for fault identification
Test condition:
Bus active && (egas_can_ed_tsperr_lls == 0)
Terminal condition: Wakeup
Voltage condition:
max (ub, u_wakeup) <= K_SMG_CAN_ED_Plus_Min

Condition for fault memory entry
Bus-off from CAN driver

Action in service
1. Delete stored DTCs from error memory, idle actuator
system test
2. Check wiring harness to idle actuator 1 and idle actuator
2, SMG control module and DME
3. Unplug SMG control module, delete stored DTCs from
error memory, conduct idle actuator system test
4. Unplug idle actuators individually, delete stored DTCs
from error memory, conduct idle actuator system test

Fault effect and breakdown warning
DSC lamp / Check Control message / power reduction/
higher idle speed / displayed engine-speed limitation to 2500
rpm / poor throttle response / MIL comes on after engine
runs 2x

Driver information
Warning light:
29-Engine malfunction

Service instruction
none