Test L: No International Standards Organization (ISO) 9141 Communications Network Communication
PINPOINT TEST L: NO INTERNATIONAL STANDARDS ORGANIZATION (ISO) 9141 COMMUNICATIONS NETWORK COMMUNICATIONL1:
L2-L5:
L6-L9:
L9-L12:
Normal Operation
The parking aid module and the restraint control module (RCM) communicate with the diagnostic tool through the ISO 9141 communications network circuit 70 (LB/WH). The anti-lock brake system (ABS) module is also on the ISO 9141 communications network, but does not utilize this network for communications with the diagnostic tool. If circuit 70 (LB/WH) becomes open or shorted to ground, communications to that module will not be possible. Check circuit 70 (LB/WH) between the parking aid module, RCM, ABS module, and the data link connector (DLC) C251. The total resistance value must not be more than 5 ohms. If the resistance is more than 5 ohms there is an open in circuit 70 (LB/WH), damage to the DLC C251, damage to the parking aid module, RCM, ABS module, or a problem in one of the in-line connectors. If, after individual checks of each circuit leading to a module show resistance values less than 5 ohms and no in-line connector issues present, the diagnostic tool data link test must be run with the module in question disconnected. If the data links diagnostics test passes with the module in question disconnected it is the source of the concern and should be removed and a new module installed.
Possible Causes
- circuit 70 (LB/WH) short to voltage, short to ground or open
- DLC C251
- RCM
- ABS module
- parking aid module (if equipped)