U121B-00-Lost Communication With Vehicle Tracking Module (Telematics Control Unit): Notes

WARNING: This page is about a different car, the 2014 Fiat 500e. However, it is still accessible from the selected car via links, so may be relevant.

For a complete wiring diagram, refer to appropriate SYSTEM WIRING DIAGRAMS article .

Fig 1: CAN B Bus Topology Diagram

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