Technical Service Bulletin SM1903 — 2020 BLUE BIRD VISION SCHOOL BUS
ELECTRICAL SYSTEM
Bulletin Details
| TSB ID | SM1903 |
| Manufacturer | |
| Vehicle | 2020 BLUE BIRD VISION SCHOOL BUS |
| Component | ELECTRICAL SYSTEM |
| Communication Date |
Bulletin Summary
Service Memorandum (SM1903) includes basic troubleshooting steps for Cummins engines with "Aftertreatment Abnormal Update Rate Fault Codes". These codes indicate either a problem with the aftertreatment battery power/ground circuits, the proprietary data link circuits, or one of the components connected to the proprietary data link. Both Cummins and Blue Bird harnesses include the proprietary data link circuits, and power/ground circuits. Blue Bird harnesses include the aftertreatment powerground circuits, and the proprietary data link circuits on the OEM side of the 14-pin crossover connector that plugs to the Cummins engine harness. The Blue Bird supplied circuits go from the 14 pin OEM crossover connector to the SCR sensor table, DPF sensor table, and the DEF tank sensor. Proprietary data link circuits DO NOT go the the diagnostic port connector located inside the cab of the bus.
About Technical Service Bulletins
A Technical Service Bulletin (TSB) is a document issued by a vehicle manufacturer to its dealers, describing a known issue with a specific vehicle or set of vehicles and the recommended procedure to fix it. Unlike recalls, TSBs are not mandatory and are typically only performed if an owner reports the related issue. However, TSBs can be an indicator of common problems with a vehicle.
Other TSBs for the 2020 BLUE BIRD VISION SCHOOL BUS
S19AG
EQUIPMENT:APPLIANCE:AIR CONDITIONER
S19ZI
SEATS
S19AB NonSchool
FUEL SYSTEM, DIESEL:STORAGE:TANK ASSEMBLY
S19AB School Bus
FUEL SYSTEM, DIESEL:STORAGE:TANK ASSEMBLY