ISO 9141 Communications Network
WARNING: This page is about a different car, the 2008 Mercury Mariner and 2008 Ford Escape. However, it is still accessible from the selected car via links, so may be relevant.
The ISO 9141 communications network is a single wire network. The ISO communications network does not permit intermodule communication and is only used for the parking aid module (PAM). When the scan tool communicates with the parking aid module, the scan tool must request all information, the module cannot initiate communications.
The ISO network operates at a maximum data transfer speed of 10 Kbps for bus messages and is designed for scan tool to module diagnostic use only.
The following fault chart describes the specific ISO 9141 network failures and their resulting symptom:
ISO 9141 NETWORK COMMUNICATION FAULT CHART
| Failure Description | Symptom |
|---|---|
| ISO circuit open | No communication |
| ISO circuit short to voltage | No communication |
| ISO circuit short to ground | No communication |
| Module loss of voltage or ground | No communication |
| Module internal failure | No communication |