Test M: No International Standards Organization (ISO) 9141 Network Communication

PINPOINT TEST M: NO INTERNATIONAL STANDARDS ORGANIZATION (ISO) 9141 NETWORK COMMUNICATION

M1-M4:

M4-M6:

M7-M9:

Normal Operation
The following modules communicate using the ISO 9141 communications network:
- restraints control module (RCM)
- fire suppression module (FSM) (if equipped)

The ISO 9141 network has a single-conductor data bus circuit 70 (LB/WH). The ISO 9141 communications network does not permit intermodule communication. When the diagnostic tool communicates to modules on the ISO 9141 communications network, the diagnostic tool must request all information or initiate module commands. The ISO 9141 communications network does not function if the wire is shorted to ground or battery voltage. Also, if one of the modules on the ISO 9141 communications network loses power or shorts internally, communications to that module fail.

Possible Causes
- ISO 9141 circuit 70 (LB/WH) open, short to ground, or short to voltage
- DLC C251
- RCM C310a
- FSM C3281a (if equipped)
- RCM
- FSM (if equipped)