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870 – AL MB Valve defect 2
Cause
Corrective action
The exhaust brake on the B-side
Y57B / MB57B cannot be
activated.
u
Contact Service.
871 – AL NOx ATO1 Communication Lost
Cause
Corrective action
The ECU can no longer detect
NOx sensor B88.1 downstream of
the LP turbocharger (A side) on
the bus.
1. Check engine wiring (→ Page 157).
2. Check NOx sensor, replace as necessary (→ Page 160).
3. Contact Service.
872 – AL EGR FlpA Wear Limit3
Cause
Corrective action
Faulty rapid reference movement
of the EGR shutoff flap on the A
side (M53.1) (always executed
after restarting the ECU).
1. Check state of battery charge (plant).
2. Contact Service.
876 – AL EGR FlpB Wear Limit3
Cause
Corrective action
Faulty rapid reference movement
of the EGR shutoff flap on the B
side (M53.2) (always executed
after restarting the ECU).
1. Check state of battery charge (plant).
2. Contact Service.
877 – AL Bypass FlpA Wear Limit3
Cause
Corrective action
Faulty rapid reference movement
of the bypass flap on the A side
(M52.1) (always executed after
restarting the ECU).
1. Check state of battery charge (plant).
2. Contact Service.
878 – AL Bypass FlpB Wear Limit3
Cause
Corrective action
Faulty rapid reference movement
of the bypass flap on the B side
(M52.2) (always executed after
restarting the ECU).
1. Check state of battery charge (plant).
2. Contact Service.
898 – AL Trican Communication Lost
Cause
Corrective action
The ECU can no longer detect the
TriCAN sensor (B90) on the bus.
1. Check engine wiring (→ Page 157).
2. Contact Service.
86 | Troubleshooting | MS150100/06E 2017-08
TIM-ID: 0000064702 - 003