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U0421-00-Implausible Data Received From Suspension Control Module

WARNING: This page is about a different car, the 2021 Jeep Grand Cherokee L. However, it is still accessible from the selected car via links, so may be relevant.

The COMMUNICATION DIAGNOSTIC PROCEDURE MUST be performed before replacing any component(s) or module(s). Perform the COMMUNICATION DIAGNOSTIC PROCEDURE. Refer to COMMUNICATION DIAGNOSTIC PROCEDURE .